Revert "Reland "[C10] PG observability hooks. (#108815)" (#110907)"
This reverts commit 7678cd22af46c9df4fb47a409d3e8ad71a6127ea.
Reverted https://github.com/pytorch/pytorch/pull/110907 on behalf of https://github.com/huydhn due to Sorry for reverting this, but macos job in trunk starts failing after this https://hud.pytorch.org/pytorch/pytorch/commit/7678cd22af46c9df4fb47a409d3e8ad71a6127ea ([comment](https://github.com/pytorch/pytorch/pull/110907#issuecomment-1756497387))
