Requests to any path in an empty GitHub repo return 200, which cause us to identify empty repos as FSHy

[masnick]

We use HEAD requests to a path on github.com to determine whether there are FSH folders in a repo. If the repo is empty, these requests will return 200 even though nothing is there.

To resolve, Util.github_repo_exists should be modified to make sure the repo isn't empty.

[masnick]

Actually using the API to get the list of branches may mitigate this in practice, but regardless it should be cleaned up so Util.github_path_exists does what it says on the tin.

[cmoesel]

If you use the GH API $org/repos call to get the list of repos from an org, you can look at the size property of the repo. It will be 0 if it is an empty repo. You may also want to consider the archived and disabled flags.