gh-143544: Fix re-entrant JSONDecodeError regression test

Author: VanshAgarwal24036

Lib/test/test_json/test_fail.py

@@ -256,7 +256,7 @@ def __call__(self, *args, **kwargs):
         ):
             # The exact exception type is not important here;
             # this test only ensures we don't crash.
-            with self.assertRaises(self.JSONDecodeError):
+            with self.assertRaises(json.JSONDecodeError):
                 json.loads('"\\uZZZZ"')