New feature motivation

As the README currently states for the GH_TOKEN variable; "Only the personal token authentication is supported". This is unfortunate, since automated rotation of PATs is not possible.

If GH-App Application Access Tokens were supported (which can be rotated via API calls), this module could be used more securely.

New feature description

The support of GH-App Application Access Tokens for authentication against Github.

New feature implementation

No response