Fix tests on Python >=3.11

Author: brianschubert

src/test_typing_extensions.py

@@ -6675,6 +6675,10 @@ def test_type_var_inheritance(self):
         self.assertFalse(isinstance(Unpack[Ts], TypeVar))
         self.assertFalse(isinstance(Unpack[Ts], typing.TypeVar))
 
+    @skipUnless(
+        sys.version_info < (3, 11),
+        "_UnpackAlias only uses __class__ trick Python <3.11"
+    )
     def test_isinstance_results_unaffected_by_presence_of_tracing_function(self):
         # See https://github.com/python/typing_extensions/issues/661