Cumsum: acc_ops (#66189)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/66189
Added acc_ops for cumsum and unit test
Test Plan: buck test glow/fb/fx/oss_acc_tracer:test_acc_tracer
Reviewed By: 842974287
Differential Revision: D31355244
fbshipit-source-id: 41490d300553b0a5d52cbc4e681bdd0cf990eb42
