Allow actions to be stored inside a sub-directory of a repository

[tobiastom]

Some action developers seem to put multiple actions into separate directories inside one repository: Example: flatpak-github-actions.

As this works with GitHub Actions, it would be nice to also be able to get update notifications for them.

[saadmk11]

Interesting I have not come across GitHub actions like this. We should support this, I'll try to add this in the next release. PR's are welcome as well :)