gh-152315: Cover bound self method call

Author: SurenNihalani

Lib/test/test_call.py

@@ -1014,6 +1014,10 @@ def test_unbound_method_with_self_keeps_missing_argument_error(self):
         with self.check_raises_type_error(msg):
             Dog.sit()
 
+    def test_instance_method_with_self_works(self):
+        """Calling an instance method with self bound should still work."""
+        self.assertIsNone(Dog().sit())
+
     def test_classmethod_missing_cls_does_not_suggest_missing_self(self):
         """A classmethod missing cls conceptually should not suggest self."""
         msg = "Dog.register_breed() takes 1 positional argument but 2 were given"