greg.tests: drop assignment to unused variables

As reported by pylint.

Fixes: GREG-16

greg/tests/test_api_person.py

@@ -15,8 +15,8 @@ class GregAPITestCase(APITestCase):
         self.client = self.get_token_client()
 
     def get_token_client(self, username="test") -> APIClient:
-        self.user, created = get_user_model().objects.get_or_create(username=username)
-        token, created = Token.objects.get_or_create(user=self.user)
+        self.user, _ = get_user_model().objects.get_or_create(username=username)
+        token, _ = Token.objects.get_or_create(user=self.user)
         client = APIClient()
         client.credentials(HTTP_AUTHORIZATION="Token {}".format(token.key))
         return client