[3/n][torch/elastic][upstream] Move torchelastic/events to torch/distributed/events (#53760)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/53760
Pull Request resolved: https://github.com/pytorch/elastic/pull/143
The diff upsteams torchelastic/events to the torch.
Test Plan:
buck test mode/dev-nosan //pytorch/elastic/torchelastic/agent/...
buck test mode/dev-nosan //caffe2/test/distributed/elastic/events/fb/...
Reviewed By: kiukchung
Differential Revision: D26932830
fbshipit-source-id: 23fc10d2ead5af7f7ed510ae0d2581cc2421cf76
