Set fixed dependency version for GitPython

[miffels]

Hey,

We've had an issue in our pipeline lately that appears to have been due to a combination of Python 3.7 on the build box and this plugin transitively pulling GitPython v3.1.20. The issue appears to be related to gitpython-developers/GitPython#1095. We were able to resolve the issue by setting the last known working version, which was 3.1.19. It's now fixed for us since we added GitPython to our own project dependencies with that version, but this might help others avoid the issue altogether. Otherwise some sort of FAQ or troubleshooting/setup guide might be helpful where people should set their own reliable version for stable builds.

Cheers!

[timvink]

Thanks a lot for digging into this and providing a PR!

There are two choices here: 1) either I fixed dependencies, and on every update re-run the tests and deploy a new version (f.e. using dependabot). 2) I set a minimal version, trust downstream releases and let the user deal with problems should they arise.

I am going for 2), because of maintenance time mainly but also to avoid forcing users into specific versions.

It also turns out that GitPython yanked the faulty release in the meantime:

So, I will close this PR. I have opened #57 to make sure I am notified of these kinds of issues earlier however.