fix flaky test for user notification task (#17676)

* fix flaky test for user notification task

followup to #17662, in batch size test... just test batch size

ordering in the query won't necessarily match ordering of usernames... so just compare call counts. the other tests ensure the right users arenotified, let this one just look at the batch size

* lint

---------

Co-authored-by: Dustin Ingram <di@users.noreply.github.com>

tests/unit/accounts/test_tasks.py

@@ -64,7 +64,7 @@ def test_notify_users_of_tos_update_respects_batch_size(
         "terms.revision": "initial",
         "terms.notification_batch_size": batch_size,
     }
-    users_to_notify = UserFactory.create_batch(20, with_verified_primary_email=True)
+    UserFactory.create_batch(max(1, batch_size * 2), with_verified_primary_email=True)
 
     send_email = pretend.call_recorder(lambda request, user: None)
     monkeypatch.setattr(tasks, "send_user_terms_of_service_updated", send_email)
@@ -75,19 +75,8 @@ def test_notify_users_of_tos_update_respects_batch_size(
 
     notify_users_of_tos_update(db_request)
 
-    assert sorted(send_email.calls, key=lambda x: x.args[1]) == sorted(
-        [pretend.call(db_request, u) for u in users_to_notify][:batch_size],
-        key=lambda x: x.args[1],
-    )
-    assert sorted(
-        user_service.record_tos_engagement.calls, key=lambda x: x.args[0]
-    ) == sorted(
-        [
-            pretend.call(u.id, "initial", TermsOfServiceEngagement.Notified)
-            for u in users_to_notify
-        ][:batch_size],
-        key=lambda x: x.args[0],
-    )
+    assert len(send_email.calls) == batch_size
+    assert len(user_service.record_tos_engagement.calls) == batch_size
 
 
 def test_notify_users_of_tos_update_does_not_renotify(