Delete bugbear from Python 2 lint. (#18192)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/18192
ghimport-source-id: 9523a09d7ec202ef08cf0ecdf48c42739ea6b0ce
Stack from [ghstack](https://github.com/ezyang/ghstack):
* **#18192 Delete bugbear from Python 2 lint.**
Signed-off-by: Edward Z. Yang <ezyang@fb.com>
Differential Revision: D14529240
fbshipit-source-id: 1a433b53dd38d1c455e8c0750d97c594ac51ef09
