Added test case for reinit (#26506)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/26506
[pytorch] [distributed] Made test forgiving to allow rpc agent to return one of the two errors.
ghstack-source-id: 90667534
Test Plan: Made sure pg based UT works.
Differential Revision: D17488899
fbshipit-source-id: 41f76cf4b4a0ca5e651a5403d6e67b639f0b9c4f
