Re-enable test_rref_context_debug_info after enforcing proper synchronization (#30994)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/30994
The flakiness we saw was due to missing barriers(), which caused
states leaked into previous or subsequent checks. This commit
attempts fix this problem by adding barriers before and after each
check.
Test Plan: Imported from OSS
Differential Revision: D18893457
Pulled By: mrshenli
fbshipit-source-id: 42bcc12efa7e6e43e2841ef23e4bc2543b0236c6
