[3.12] Update the expected bytecode magic in test_importlib.test_util (…

…python#107626)

Update the expected bytecode magic in test_importlib.test_util to the final
3.12 magic number. From now on it's not allowed to change for any 3.12
release.

Lib/test/test_importlib/test_util.py

@@ -634,7 +634,7 @@ def test_magic_number(self):
         # stakeholders such as OS package maintainers must be notified
         # in advance. Such exceptional releases will then require an
         # adjustment to this test case.
-        EXPECTED_MAGIC_NUMBER = 3495
+        EXPECTED_MAGIC_NUMBER = 3531
         actual = int.from_bytes(importlib.util.MAGIC_NUMBER[:2], 'little')
 
         msg = (