closes bpo-38648: Remove double tp_free slot in Python-ast.c. (GH-17002)

This looks like a typo due to copy-paste.

Author: tekknolagi

Parser/asdl_c.py

@@ -751,7 +751,6 @@ def visitModule(self, mod):
     {Py_tp_init, ast_type_init},
     {Py_tp_alloc, PyType_GenericAlloc},
     {Py_tp_new, PyType_GenericNew},
-    {Py_tp_free, PyType_GenericNew},
     {Py_tp_free, PyObject_GC_Del},
     {0, 0},
 };