[pre-commit.ci] pre-commit autoupdate

[pre-commit-ci]

updates:

• https://github.com/ambv/black → https://github.com/psf/black
• github.com/psf/black: 20.8b1 → 21.9b0
• github.com/pre-commit/mirrors-prettier: v2.2.1 → v2.4.1
• github.com/asottile/reorder_python_imports: v2.4.0 → v2.6.0
• github.com/pre-commit/pre-commit-hooks: v3.4.0 → v4.0.1
• https://gitlab.com/pycqa/flake8 → https://github.com/PyCQA/flake8
• github.com/PyCQA/flake8: 3.8.4 → 3.9.2

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