Update .gitlab-ci.yml

1 job for master in 30 seconds (queued for 1 second)
Name Stage Failure
failed
build Test
[ERROR] /builds/gitlab/hft_gitlab/regionchooser/src/main/java/eu/simstadt/regionchooser/RegionChooserBrowser.java:[153,9] method does not override or implement a method from a supertype
[ERROR] -> [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/MojoFailureException
ERROR: Job failed: exit code 1