Add warning comment for unpickling in test_template_registry.py to emphasize security concerns

Author: BrianMichell

tests/unit/v1/templates/test_template_registry.py

@@ -325,7 +325,8 @@ def test_template_is_pickleable(self) -> None:
 
         # Pickle and unpickle it
         pickled = pickle.dumps(retrieved)
-        unpickled = pickle.loads(pickled)
+        # You should only ever unpickle with trusted data!
+        unpickled = pickle.loads(pickled)  # noqa: S301
 
         # Should be different objects
         assert unpickled is not retrieved