3rd party auth removal cleanup

- Sequentiallize auth config removal migrations
- Remove references to third party auth
- update license files
- lint fix
- Remove unneeded docs
- Remove unreferenced file
- Remove social auth references from docs
- Remove rest of sso dir
- Remove references to third part auth in docs
- Removed screenshots of UI listing removed settings
- Remove AuthView references
- Remove unused imports
...

Co-Authored-By: jessicamack <21223244+jessicamack@users.noreply.github.com>

requirements/README.md

@@ -49,18 +49,6 @@ Make sure to delete the old tarball if it is an upgrade.
 Anything pinned in `*.in` files involves additional manual work in
 order to upgrade. Some information related to that work is outlined here.
 
-### social-auth-app-django
-
-django-social keeps a list of backends in memory that it gathers
-based on the value of `settings.AUTHENTICATION_BACKENDS` *at import time*:
-https://github.com/python-social-auth/social-app-django/blob/c1e2795b00b753d58a81fa6a0261d8dae1d9c73d/social_django/utils.py#L13
-
-Our `settings.AUTHENTICATION_BACKENDS` can *change*
-dynamically as settings are changed (i.e., if somebody
-configures Github OAuth2 integration), so we need to
-_overwrite_ this in-memory value at the top of every request so
-that we have the latest version
-
 ### django-oauth-toolkit
 
 Versions later than 1.4.1 throw an error about id_token_id, due to the