[pre-commit.ci] pre-commit autoupdate

updates:
- [github.com/psf/black: 21.9b0 → 21.10b0](psf/black@21.9b0...21.10b0)

Author: pre-commit-ci[bot]

.pre-commit-config.yaml

@@ -6,7 +6,7 @@ repos:
   hooks:
   - id: trailing-whitespace
 - repo: https://github.com/psf/black
-  rev: 21.9b0
+  rev: 21.10b0
   hooks:
   - id: black
 - repo: https://github.com/PyCQA/flake8