Always import importlib.util

Summary:
An upstream change uses importlib.util after only importing importlib: python/cpython#138510

In normal CPython this gets mported via runpy so it pretty much always available. In our dev environment we don't import it, so this just makes sure it gets imported for test purposes.

Reviewed By: yoney

Differential Revision: D82228954

fbshipit-source-id: 86e1cd776d2a3819ffff9c6069613d141ab88dd1

Author: DinoV

cinderx/TestScripts/cinder_test_runner312.py

@@ -30,6 +30,9 @@
 import types
 import unittest
 
+# CPython always imports this on startup, but cinder's dev environment doesn't
+from importlib import util
+
 from pathlib import Path
 
 from typing import Dict, IO, Iterable, List, Optional, Set, Tuple