fix the readme link (#56269)
Summary:
Fixes #{issue number}
Pull Request resolved: https://github.com/pytorch/pytorch/pull/56269
Reviewed By: VitalyFedyunin
Differential Revision: D27824048
Pulled By: ejguan
fbshipit-source-id: 8d5ecbdf502ae8bf8e807b55f6daeb3ff234aa62
