[TensorPipe] Silence some more harmless warnings (#40094)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/40094
In #39182 we already silenced a few warnings when they were caused by expected errors, but left one case out, namely errors on an incoming pipe. The idea was to introduce a "proper" way of detecting these, for example by having the remote end send an empty message to indicate an intentional shutdown. I don't know if we'll have time to do that in time for v1.6, so as a temporary solution I'm implementing some approximation which, although imperfect, should cover most errors. I also made the warning message less scary by adding a clarification.
ghstack-source-id: 105969540
Test Plan: Unit tests
Differential Revision: D22067818
fbshipit-source-id: b2e2a37d633f21bca4a2873a05ad92b853dde079
