Remove flake8 E303 (too many blank lines) (#20225)
Summary:
similar to too few blank lines, I feel like this is not important enough to warrant breaking signal for all linters when it's violated.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/20225
Differential Revision: D15243480
Pulled By: suo
fbshipit-source-id: 37cdc18daf09e07081e42b69c72d331d81660217
