properly whitelist clang-format in CI (#37122)
Summary: Pull Request resolved: https://github.com/pytorch/pytorch/pull/37122
Test Plan: Imported from OSS
Reviewed By: shannonzhu
Differential Revision: D21194505
Pulled By: suo
fbshipit-source-id: d756c5291535ac1aefbbad57b38f324e42e2c2f7
