Clang-format ProcessGroupMPI.cpp (#55969)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/55969
Per title
ghstack-source-id: 126453717
Test Plan: N/A
Reviewed By: zhaojuanmao
Differential Revision: D27752173
fbshipit-source-id: e5069b91d699b9d02b12e5dab5e62007dbcee9f0
