Revert D33820822: [pytorch][PR] Run the pr-label check on PR closed action and validate closed_by
Test Plan: revert-hammer
Differential Revision:
D33820822 (https://github.com/pytorch/pytorch/commit/e020414cb25cd763103f77a10c6225ce27cbbb6e)
Original commit changeset: 373ffcbc2bca
Original Phabricator Diff: D33820822 (https://github.com/pytorch/pytorch/commit/e020414cb25cd763103f77a10c6225ce27cbbb6e)
fbshipit-source-id: e9b4cf7f3861c8a383b9ab52f55a6ca3fe8b7fb2
(cherry picked from commit 43b9277c235a5bc4bcaa71347432c56f04a096c9)
