bpo-46263: Fix second location that needs MALLOC_CONF on FreeBSD (GH-30440)

Automerge-Triggered-By: GH:tiran
(cherry picked from commit c9137d4)

Co-authored-by: Christian Heimes <christian@python.org>

Author: miss-islington

Lib/test/test_capi.py

@@ -926,7 +926,11 @@ def check_pyobject_is_freed(self, func_name):
             except _testcapi.error:
                 os._exit(1)
         ''')
-        assert_python_ok('-c', code, PYTHONMALLOC=self.PYTHONMALLOC)
+        assert_python_ok(
+            '-c', code,
+            PYTHONMALLOC=self.PYTHONMALLOC,
+            MALLOC_CONF="junk:false",
+        )
 
     def test_pyobject_null_is_freed(self):
         self.check_pyobject_is_freed('check_pyobject_null_is_freed')