Fix flaky organization model test

Compare sets instead of list to avoid any issues around ordering.

tests/unit/lms/models/organization_test.py

@@ -19,7 +19,7 @@ def test_application_instance_relationship(
     ):
         db_session.flush()
 
-        assert organization.application_instances == application_instances
+        assert set(organization.application_instances) == set(application_instances)
         for application_instance in application_instances:
             assert application_instance.organization == organization