Update .gitlab-ci.yml file -- releases only for master and for valid tag format

.gitlab-ci.yml

@@ -71,10 +71,13 @@ publish:
 fatjar:
   stage: fatjar
   rules:
-    - if: $CI_COMMIT_TAG
-  only:
-    refs:
-      - master
+    # Do no allow manually triggered pipelines to prevent duplicates!
+    # Instead rerun the pipeline created with the last push
+    - if: $CI_PIPELINE_SOURCE != "push"
+      when: never
+    # Only execute when a valid version tag like v1.0, 2.3 or similar is given
+    # Required is always one point like 1.0
+    - if:  $CI_COMMIT_REF_NAME == "master" && $CI_COMMIT_TAG =~ /^v?[0-9]+[.][0-9]+([.][0-9]+)?$/
   before_script:
     - echo $CI_JOB_ID
     # Writing FATJAR_JOB_ID variable to environment file, as variable is needed in the release stage.
@@ -94,10 +97,13 @@ fatjar:
 release:
   stage: release
   rules:
-    - if: $CI_COMMIT_TAG                  # Run this job when a git tag is created manually
-  only:
-    refs:
-      - master
+    # Do no allow manually triggered pipelines to prevent duplicates!
+    # Instead rerun the pipeline created with the last push
+    - if: $CI_PIPELINE_SOURCE != "push"
+      when: never
+    # Only execute when a valid version tag like v1.0, 2.3 or similar is given
+    # Required is always one point like 1.0
+    - if:  $CI_COMMIT_REF_NAME == "master" && $CI_COMMIT_TAG =~ /^v?[0-9]+[.][0-9]+([.][0-9]+)?$/
   needs:
     - job: fatjar
       artifacts: true