[3.13] gh-120811: Fix reference leak upon _PyContext_Exit failure (GH-120812) (#120843)

gh-120811: Fix reference leak upon `_PyContext_Exit` failure (GH-120812)
(cherry picked from commit aed31beca9)

Co-authored-by: Peter <zintensitydev@gmail.com>
Co-authored-by: Kumar Aditya <kumaraditya@python.org>

Python/context.c

@@ -661,6 +661,7 @@ context_run(PyContext *self, PyObject *const *args,
         ts, args[0], args + 1, nargs - 1, kwnames);
 
     if (_PyContext_Exit(ts, (PyObject *)self)) {
+        Py_XDECREF(call_result);
         return NULL;
     }