Don't open second MR for gradle (Closes: #914)
Don't open second MR for gradle (Closes: #914)

Traceback (most recent call last):
  File "/builds/fdroid/fdroidserver/./tests/gradle-release-checksums.py", line 130, in <module>
    mr = project.mergerequests.create({
  File "/usr/lib/python3/dist-packages/gitlab/exceptions.py", line 281, in wrapped_f
    raise error(e.error_message, e.response_code, e.response_body) from e
gitlab.exceptions.GitlabCreateError: 409: ['Another open merge request already exists for this source branch: !1064']

fdroidtravis/fdroidserver,f-droid/fdroidserver,f-droid/fdroidserver,fdroidtravis/fdroidserver,fdroidtravis/fdroidserver,fdroidtravis/fdroidserver,f-droid/fdroidserver,f-droid/fdroidserver,f-droid/fdroidserver