Feature request: allow making releases from certain branches only.

[yakutovicha]

Use case.

I've just mistakenly made a release from the wrong branch. After the tag was pushed to GitHub, our automated release machinery released the new version on GitHub and PyPI.

It would be great to have some safeguard mechanism to prevent this from happening.

Proposed solution.

It would be great to have an allowed branch pattern. Something like this:

    [bumpver]
    ...
    allowed_branch_pattern = "main"  # or similar
    ...

[mbarkhau]

I would accept a PR for this. Preferably using comma separation and glob syntax.

[bumpver]
...
allowed_branches = "master,main,release-*"