Return None indicates auth does not apply

* Returning a tuple indicates the user auth failure. We want "auth does
  not apply".

ansible_base/jwt_consumer/common/auth.py

@@ -281,7 +281,7 @@ def authenticate(self, request):
 
  return user, None
  else:
- return None, None
+ return None
 
  def process_user_data(self, user, token):
  common_auth = JWTCommonAuth(self.map_fields)

test_app/tests/jwt_consumer/common/test_auth.py

@@ -342,10 +342,10 @@ def test_authenticate(self, jwt_token, django_user_model, mocked_http, test_encr
 
  def test_authenticate_no_user(self, user):
  with mock.patch('ansible_base.jwt_consumer.common.auth.JWTCommonAuth.parse_jwt_token') as mock_parse:
- mock_parse.return_value = (None, {})
+ mock_parse.return_value = (None, None)
  jwt_auth = JWTAuthentication()
- created_user, _ = jwt_auth.authenticate(mock.MagicMock())
- assert created_user is None
+ auth_provided = jwt_auth.authenticate(mock.MagicMock())
+ assert auth_provided is None
 
  def test_process_user_data(self):
  with mock.patch("ansible_base.jwt_consumer.common.auth.JWTCommonAuth.map_user_fields") as mock_inspect: