Release Action: Pin GitPython

[annehaley]

Addresses this CI failure.

GitPython just released 3.1.60, which includes a breaking change with the removal of Actor.name_email_regex, which is needed by python semantic release. (This commit has the change).

This PR pins GitPython to 3.1.59 in the release action.

[BryonLewis]

I think this is fine for now. I would watch the issue on python-semantic-release: python-semantic-release/python-semantic-release#1476
Looks like there is a PR an fix already so an upgrade to it in the future should prevent needing to pin GitPython. Although I'm not sure if the new fix of just directly recreating that regular expression avoids the fundamental reason why it was removed in GitPython.

[annehaley]

Yeah with the creation of that PR in python-semantic-release, I'll wait a bit before merging this. If the upstream is fixed quickly, then we can just rerun the job and close this if it succeeds.

[annehaley]

GitPython released 3.1.61 this morning, which brings back (but deprecates) Actor.name_email_regex. Our release job works again. The discussion on the python-semantic-release PR linked above will decide how to deal with the future removal.