Fixes pr-labels workflow trigger (#71871)
Summary:
Fixes pr-labels workflow trigger
Pull Request resolved: https://github.com/pytorch/pytorch/pull/71871
Reviewed By: anjali411, janeyx99
Differential Revision: D33796618
Pulled By: atalman
fbshipit-source-id: b93595b62ee831a40578e524e499e0ddd6affeb8
(cherry picked from commit 3080548ff3cbd9b74621602d4e211e5ea0034f5c)
