[Easy] Format DDP error (#71802)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/71802
Per title
ghstack-source-id: 147753213
Test Plan: CI
Reviewed By: zhaojuanmao
Differential Revision: D33774513
fbshipit-source-id: f798ea9f63aa1ae573c6b012cc6e749d126dedea
(cherry picked from commit 631157b3ea834c499cea740df6877644b8e27a10)
