BOM-1264: add third-party-auth scope and usage (#23135)

* WIP: add third-party-auth scope and usage

BOM-1264


* Fix tests now that we do permissions in a more standard way.

Rather than manually setting the permission class we previously
explicitly raised a PermissionDenied exception.  The way DRF
permissoning logic works, if we use the WWW-Authenticate header in the
highest priority auth class, it will return a 401 instead of a 403.


* Added test to make sure having permissions gives access to user mapping api

* Test new filters logic.

Ensure that the filters we add to the application access model make it
into the JWT correctly.

* quality fix

* quality fix

* disable pylint warning

* quality fix

* fix indent prob

Co-authored-by: Feanil Patel <feanil@edx.org>
Co-authored-by: Manjinder Singh <49171515+jinder1s@users.noreply.github.com>