fix fsdp overlap flaky test (#68415)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/68415
remove e4["cpu_iter"] from short list as cpu may take some time to queue both compute and all-gather.
close #68391
ghstack-source-id: 143478769
Test Plan: unit tests
Reviewed By: rohan-varma
Differential Revision: D32457334
fbshipit-source-id: baeedfb628ce4554a1ef365c3a2de27b8884f6d4
