Configurable git author

[mircea-pavel-anton]

Currently, it seems that this backend defaults to using username@hostname for the git author. I would like to use this in CI and commit as my github app using a custom token generated in that workflow.

[mircea-pavel-anton]

Another valid use-case for this is having a repository with branch protection that forbids pushing to the main branch directly. We could then have a service account specified in the bypass list and configured as the git author for this backend such that it can update the state