Update CODEOWNERS for distributed rpc framework. (#29788)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/29788
ghstack-source-id: 93889545
Test Plan: waitforbuildbot
Differential Revision: D18498997
fbshipit-source-id: e1419f1a487f7fe4d5f6af9de66e930da067b70e
