* Azure AD users should not be able to change their password
* Multiple auth changes
Moving get_external_user function into awx.sso.common
Altering get_external_user to not look at current config, just user object values
Altering how api/conf.py detects external auth config (and making reusable function in awx.sso.common)
Altering logic in api.serializers in _update_pasword to use awx.sso.common
* Adding unit tests
---------
Co-authored-by: John Westcott IV <john.westcott.iv@redhat.com>