🔥 Exterminate `__builtin__` import from tests (#82569)

This patch removes an import fallback that was only executed under
Python 2. Now that we don't run tests against that runtime, it
generates an uncovered line. Dropping it will slightly increase the
coverage metric as a side effect.

test/units/module_utils/basic/test_set_mode_if_different.py

@@ -5,16 +5,12 @@
 
 from __future__ import annotations
 
+import builtins
 import errno
 import os
 
 from itertools import product
 
-try:
-    import builtins
-except ImportError:
-    import __builtin__ as builtins
-
 import pytest