fix: use master or main for production env

templates/gitlab-ci-maven.yml

@@ -18,7 +18,7 @@ variables:
   MAVEN_IMAGE: "maven:latest"
 
   # default production ref name (pattern)
-  PROD_REF: '/^master$/'
+  PROD_REF: '/^(master|main)$/'
   # default integration ref name (pattern)
   INTEG_REF: '/^develop$/'