More OAuth/OpenID changes for the scheduler:

More OAuth/OpenID changes for the scheduler:

- Instead of treating the bearer token as a JWT, use the userinfo endpoint
  (via cupsOAuthGetUserId) to get the user information and (as a side-effect)
  validate the bearer token.
- Set the verified AuthType when get have a valid token.
- Support OAuth group files relative to the cupsd.conf file.