[pytorch] Move signal handler test to internal codebase (#60394)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/60394
Move signal handler test to internal codebase
Github issue: https://github.com/pytorch/pytorch/issues/60260
Test Plan:
buck test mode/dev-nosan //caffe2/test/distributed/elastic/multiprocessing:api_test
buck test mode/dev-nosan //caffe2/torch/distributed/elastic/multiprocessing/fb/test:api_test
Reviewed By: cbalioglu
Differential Revision: D29273160
fbshipit-source-id: e4ae72f7f6d54cbba324119fce7446a30a6c37c9
