Error during deploy maven artifact to private gitlab project

A customer is facing the problem below where he would like to deploy to his private project as maven dependency. His pom.xml looks like this :

<project
    xmlns="http://maven.apache.org/POM/4.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>io.new10</groupId>
    <artifactId>offerServiceClient</artifactId>
    <packaging>jar</packaging>
    <name>offerServiceClient</name>
    <version>1.0.0-2018-12-19-13-00-12</version>
    <url>https://git.new10.com/new10/offer-service/pipelines</url>
    <description>Swagger generated API Client for Offer Service API</description>
    <repositories>
        <repository>
            <id>maven-central</id>
            <url>http://repo1.maven.org/maven2</url>
        </repository>
        <repository>
            <id>gitlab-maven</id>
            <url>https://gitlab.com/api/v4/projects/9266897/packages/maven</url>
        </repository>
    </repositories>
    <distributionManagement>
        <repository>
            <id>gitlab-maven</id>
            <url>https://gitlab.com/api/v4/projects/9266897/packages/maven</url>
        </repository>
        <snapshotRepository>
            <id>gitlab-maven</id>
            <url>https://gitlab.com/api/v4/projects/9266897/packages/maven</url>
        </snapshotRepository>
    </distributionManagement>
    <developers>
        <developer>
            <name>NAME</name>
            <email>EMAIL</email>
            <organization>ORG</organization>
            <organizationUrl>URL</organizationUrl>
        </developer>
    </developers>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-enforcer-plugin</artifactId>
                <version>3.0.0-M1</version>
                <executions>
                    <execution>
                        <id>enforce-maven</id>
                        <goals>
                            <goal>enforce</goal>
                        </goals>
                        <configuration>
                            <rules>
                                <requireMavenVersion>
                                    <version>2.2.0</version>
                                </requireMavenVersion>
                            </rules>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-plugin</artifactId>
                <version>2.12</version>
                <configuration>
                    <systemProperties>
                        <property>
                            <name>loggerPath</name>
                            <value>conf/log4j.properties</value>
                        </property>
                    </systemProperties>
                    <argLine>-Xms512m -Xmx1500m</argLine>
                    <parallel>methods</parallel>
                    <forkMode>pertest</forkMode>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-dependency-plugin</artifactId>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>copy-dependencies</goal>
                        </goals>
                        <configuration>
                            <outputDirectory>${project.build.directory}/lib</outputDirectory>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
            <!-- attach test jar -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <version>2.2</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>jar</goal>
                            <goal>test-jar</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration></configuration>
            </plugin>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>build-helper-maven-plugin</artifactId>
                <version>1.10</version>
                <executions>
                    <execution>
                        <id>add_sources</id>
                        <phase>generate-sources</phase>
                        <goals>
                            <goal>add-source</goal>
                        </goals>
                        <configuration>
                            <sources>
                                <source>
                                src/main/java</source>
                            </sources>
                        </configuration>
                    </execution>
                    <execution>
                        <id>add_test_sources</id>
                        <phase>generate-test-sources</phase>
                        <goals>
                            <goal>add-test-source</goal>
                        </goals>
                        <configuration>
                            <sources>
                                <source>
                                src/test/java</source>
                            </sources>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-javadoc-plugin</artifactId>
                <version>2.10.4</version>
                <executions>
                    <execution>
                        <id>attach-javadocs</id>
                        <goals>
                            <goal>jar</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-source-plugin</artifactId>
                <version>2.2.1</version>
                <executions>
                    <execution>
                        <id>attach-sources</id>
                        <goals>
                            <goal>jar-no-fork</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>
    <profiles>
        <profile>
            <id>sign-artifacts</id>
            <build>
                <plugins>
                    <plugin>
                        <groupId>org.apache.maven.plugins</groupId>
                        <artifactId>maven-gpg-plugin</artifactId>
                        <version>1.5</version>
                        <executions>
                            <execution>
                                <id>sign-artifacts</id>
                                <phase>verify</phase>
                                <goals>
                                    <goal>sign</goal>
                                </goals>
                            </execution>
                        </executions>
                    </plugin>
                </plugins>
            </build>
        </profile>
    </profiles>
    <dependencies>
        <dependency>
            <groupId>io.swagger</groupId>
            <artifactId>swagger-annotations</artifactId>
            <version>${swagger-core-version}</version>
        </dependency>
        <dependency>
            <groupId>com.squareup.okhttp</groupId>
            <artifactId>okhttp</artifactId>
            <version>${okhttp-version}</version>
        </dependency>
        <dependency>
            <groupId>com.squareup.okhttp</groupId>
            <artifactId>logging-interceptor</artifactId>
            <version>${okhttp-version}</version>
        </dependency>
        <dependency>
            <groupId>com.google.code.gson</groupId>
            <artifactId>gson</artifactId>
            <version>${gson-version}</version>
        </dependency>
        <dependency>
            <groupId>io.gsonfire</groupId>
            <artifactId>gson-fire</artifactId>
            <version>${gson-fire-version}</version>
        </dependency>
        <!-- test dependencies -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>${junit-version}</version>
            <scope>test</scope>
        </dependency>
    </dependencies>
    <properties>
        <java.version>1.8</java.version>
        <maven.compiler.source>${java.version}</maven.compiler.source>
        <maven.compiler.target>${java.version}</maven.compiler.target>
        <gson-fire-version>1.8.0</gson-fire-version>
        <swagger-core-version>1.5.18</swagger-core-version>
        <okhttp-version>2.7.5</okhttp-version>
        <gson-version>2.8.1</gson-version>
        <maven-plugin-version>1.0.0</maven-plugin-version>
        <junit-version>4.12</junit-version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
</project>

His settings.xml file looks like this :

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<settings
    xmlns="http://maven.apache.org/SETTINGS/1.0.0"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd">
    <servers>
        <server>
            <id>>gitlab-maven</id>
            <configuration>
                <httpHeaders>
                    <property>
                        <name>Private-Token</name>
                        <value>{env.GITLAB_PRIVATE_TOKEN}</value>
                    </property>
                </httpHeaders>
            </configuration>
        </server>
    </servers>
    <mirrors>
        <mirror>
            <id>UK</id>
            <name>UK Central</name>
            <url>http://uk.maven.org/maven2</url>
            <mirrorOf>central</mirrorOf>
        </mirror>
        <mirror>
            <id>>gitlab-maven</id>
            <name>Gitlab Maven</name>
            <url>https://gitlab.com/api/v4/projects/9266897/packages/maven</url>
            <mirrorOf>central</mirrorOf>
        </mirror>
    </mirrors>
</settings>

When he run mvn deploy he gets the following error :

mvn deploy -U 
[INFO] Scanning for projects... 
[INFO] 
[INFO] --------------------< io.new10:offerServiceClient >--------------------- 
[INFO] Building offerServiceClient 1.0.0-2018-12-19-13-00-12 
[INFO] --------------------------------[ jar ]--------------------------------- 
Downloading from 9266897: https://gitlab.com/api/v4/projects/9266897/packages/maven/org/apache/maven/plugins/maven-enforcer-plugin/3.0.0-M1/maven-enforcer-plugin-3.0.0-M1.pom 
[WARNING] The POM for org.apache.maven.plugins:maven-enforcer-plugin:jar:3.0.0-M1 is missing, no dependency information available 
Downloading from 9266897: https://gitlab.com/api/v4/projects/9266897/packages/maven/org/apache/maven/plugins/maven-enforcer-plugin/3.0.0-M1/maven-enforcer-plugin-3.0.0-M1.jar 
[INFO] ------------------------------------------------------------------------ 
[INFO] BUILD FAILURE 
[INFO] ------------------------------------------------------------------------ 
[INFO] Total time: 1.634 s 
[INFO] Finished at: 2018-12-19T13:39:49+01:00 
[INFO] ------------------------------------------------------------------------ 
[ERROR] Plugin org.apache.maven.plugins:maven-enforcer-plugin:3.0.0-M1 or one of its dependencies could not be resolved: Could not find artifact org.apache.maven.plugins:maven-enforcer-plugin:jar:3.0.0-M1 in 9266897 (https://gitlab.com/api/v4/projects/9266897/packages/maven) -> [Help 1] 
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch. 
[ERROR] Re-run Maven using the -X switch to enable full debug logging. 
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles: 
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/PluginResolutionException
 

ZD: https://gitlab.zendesk.com/agent/tickets/110525

@dzaporozhets your thoughts on this?

Edited by Arihant