[pytorch] Minor: boilerplate to propagate errors in request_callback_impl (#32556)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/32556
Out of caution, avoid assuming that there's never a failure in a couple of
request_calback_impl case handlers, but rather propagate the error.
ghstack-source-id: 97128697
Test Plan: buck test mode/dev-nosan caffe2/test/...
Differential Revision: D19544685
fbshipit-source-id: 67c55626960bd42a5b0dec7841e8ba44ab059eb9
