Enable EXE001 flake8 check. (#27560)
Summary:
According to https://github.com/pytorch/pytorch/issues/27285 , seems we do not intend to use shebang as an indication of Python version, thus
we enable EXE001 flake8 check.
For violations, we either remove shebang from non-executable Python scripts or grant them executable permission.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/27560
Differential Revision: D17831782
Pulled By: ezyang
fbshipit-source-id: 6282fd3617b25676a6d959af0d318faf05c09b26
