Add temporary workaround for issue 139400

Author: hartwork

Lib/test/test_pyexpat.py

@@ -887,6 +887,15 @@ def test_set_activation_threshold__fail_for_subparser(self):
         setter = functools.partial(self.set_activation_threshold, subparser)
         self.assert_root_parser_failure(setter, 12345)
 
+        # NOTE: This is a workaround for issue
+        #       https://github.com/python/cpython/issues/139400
+        #       that can be dropped once pull request
+        #       https://github.com/python/cpython/pull/139403
+        #       has been merged.
+        del setter
+        del subparser
+        del parser
+
     @abc.abstractmethod
     def test_set_maximum_amplification__amplification_exceeded(self):
         """Test when the amplification factor is exceeded."""
@@ -921,6 +930,15 @@ def test_set_maximum_amplification__fail_for_subparser(self):
         setter = functools.partial(self.set_maximum_amplification, subparser)
         self.assert_root_parser_failure(setter, 123.45)
 
+        # NOTE: This is a workaround for issue
+        #       https://github.com/python/cpython/issues/139400
+        #       that can be dropped once pull request
+        #       https://github.com/python/cpython/pull/139403
+        #       has been merged.
+        del setter
+        del subparser
+        del parser
+
 
 @unittest.skipIf(expat.version_info < (2, 7, 2), "requires Expat >= 2.7.2")
 class MemoryProtectionTest(AttackProtectionTestBase, unittest.TestCase):