add lock for ncclCommAbort (#31901)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/31901
ncclCommAbort is not thread safe, so adding a lock for it
ghstack-source-id: 96829715
Test Plan: unit tests
Differential Revision: D19293869
fbshipit-source-id: 711b4a07605d6e5a81577247d2f90a78041c1809
