I stepped back from maintaining the GitLab plugin a little over a year ago, and in the meantime Marky Jackson-Taulia was maintaining it. He put out one release successfully, but then the release got into a broken state and between that and his limited availability, we didn't make any further progress. Since he is now taking a break from open source work, and since there are some bug fixes on the plugin that users have been waiting on for a long time, I decided to try and get a release out to at least bring it up to date. Currently all tests pass, but when I run 'mvn release:prepare release:perform' it fails with the attached errors.
A couple of other things of note: the last successful release in Artifactory is 1.5.13, which was the first and only one that Marky was able to do. Since then GitHub shows tags/releases up to 1.5.17, but none of these ever made it to the update center. I expect 1.5.18 to be the next valid release. But you'll notice that in the release process we seem to check out the tag 1.5.15 - I have no idea why.
Any pointers on how to get this back on track would be appreciated :)