Update Autograd Export Docs (#56594) (#59534)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/59534
Update autograd export docs
Test Plan: Imported from OSS
Reviewed By: nikithamalgifb, ansley
Differential Revision: D29046606
Pulled By: SplitInfinity
fbshipit-source-id: 36057f6bdfd3e5c071dbca05d327de7952904120
Co-authored-by: neginraoof <neginmr@utexas.edu>
