[Refactoring] make transformations return whether graph is modified (#54777)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/54777
Updated RemoveListMutation, PeepholeOptimizedListIdoms,
LoopUnrolling, PeepholeOptimization to return whether graph is
modified after transformation, PeepholeAliasSensitivity
Test Plan: Imported from OSS
Reviewed By: bertmaher
Differential Revision: D27412105
fbshipit-source-id: 0c1520bc34f6bd59acd83d98bed58897376eac41
