Prepare commit message hook fails when using reftable refstorage

[killerkiara]

https://github.com/code-supply/rusty-git-mob/blob/main/src/prepare_commit_message.rs#L29 needs to know the branch name.

The branch name is determined by a rust binding to libgit2 which does not support git refstorage = reftable.

So, if you have your git refstorage set to reftable, you will not see your co-author name in the commit message when running:

git mob xx
git commit -m 'poo'

(me and @craigfurman discovered this by chance starting from a branch with a capitalised name...)

[camelpunch]

Sounds like a hard one to fix without changing the library, or deciding to shell out. Any thoughts?

[camelpunch]

Maybe we should wait for libgit2/libgit2#7117