bpo-47164: Add _PyCFunction_CAST() macro (GH-32192)

Use the macro in C files of the Python/ directory.

Python/traceback.c

@@ -149,7 +149,7 @@ tb_next_set(PyTracebackObject *self, PyObject *new_next, void *Py_UNUSED(_))
 
 
 static PyMethodDef tb_methods[] = {
-   {"__dir__", (PyCFunction)tb_dir, METH_NOARGS},
+   {"__dir__", _PyCFunction_CAST(tb_dir), METH_NOARGS},
    {NULL, NULL, 0, NULL},
 };