Publish the JAR to the GitLab Maven Repository

Test plan

Install the Kotlin compiler, create the file ci.main.kts:

#!/usr/bin/env kotlin

@file:Repository("https://gitlab.com/api/v4/projects/33995298/packages/maven")
@file:DependsOn("opensavvy:gitlab-ci.kt:0.1.0-post.18+457b36dcec")

import opensavvy.gitlab.ci.*
import opensavvy.gitlab.ci.script.shell

gitlabCi {
    val test by job {
        script {
            shell("echo 'Hello world!'")
        }
    }
}.println()

Enable the execution rights, then execute as a regular script.

Closes #1 (closed)