Merge pull request #376 from sass/pre-commit-ci-update-config

[pre-commit.ci] pre-commit autoupdate

Author: asottile

.pre-commit-config.yaml

@@ -12,7 +12,7 @@ repos:
     -   id: flake8
         exclude: ^docs/conf.py
 -   repo: https://github.com/asottile/pyupgrade
-    rev: v2.29.1
+    rev: v2.31.0
     hooks:
     -   id: pyupgrade
         args: [--py36-plus]