Use ignore=dirty in submodules. (#20135)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/20135
ghimport-source-id: 73a07e07ed9485f80374262de2fb9b87e687a47a
Differential Revision: D15214187
Pulled By: zdevito
fbshipit-source-id: 2f2272f0ee7dad3935e6c31897a0b635b4e66133
