[amimetic]

I tried this and doesn't seem to work; though unclear what permissions I should be granting it, so possibly that is the issue.

[alex-titarenko]

You need only "Contents" Read and write permissions. Make sure when you generate fine-grained personal access tokens on the following page: https://github.com/settings/personal-access-tokens/new you select your desired repo (because it defaults to public repos and that will not work).