gh-71339: Use new assertion methods in test_enum

Author: srinivasreddy

Lib/test/test_enum.py

@@ -3256,7 +3256,7 @@ class MyIntFlag(int, Flag):
             ONE = 1
             TWO = 2
             FOUR = 4
-        self.assertIsInstance(MyIntFlag.ONE | MyIntFlag.TWO, MyIntFlag, MyIntFlag.ONE | MyIntFlag.TWO)
+        self.assertIsInstance(MyIntFlag.ONE | MyIntFlag.TWO, (MyIntFlag, MyIntFlag.ONE | MyIntFlag.TWO))
         self.assertIsInstance(MyIntFlag.ONE | 2, MyIntFlag)
 
     def test_int_flags_copy(self):