[pre-commit.ci] pre-commit autoupdate (#700)

updates:
- [github.com/PyCQA/flake8: 3.9.2 → 4.0.1](PyCQA/flake8@3.9.2...4.0.1)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

.pre-commit-config.yaml

@@ -12,7 +12,7 @@ repos:
         args: ["--target-version=py36"]
 
   - repo: https://github.com/PyCQA/flake8
-    rev: 3.9.2
+    rev: 4.0.1
     hooks:
       - id: flake8
         language_version: python3.8