Issue #26200: Added Py_SETREF and replaced Py_XSETREF with Py_SETREF

in places where Py_DECREF was used.

Python/errors.c

@@ -311,9 +311,9 @@ finally:
         --tstate->recursion_depth;
         /* throw away the old exception and use the recursion error instead */
         Py_INCREF(PyExc_RecursionError);
-        Py_XSETREF(*exc, PyExc_RecursionError);
+        Py_SETREF(*exc, PyExc_RecursionError);
         Py_INCREF(PyExc_RecursionErrorInst);
-        Py_XSETREF(*val, PyExc_RecursionErrorInst);
+        Py_SETREF(*val, PyExc_RecursionErrorInst);
         /* just keeping the old traceback */
         return;
     }