[pre-commit.ci] pre-commit autoupdate

[pre-commit-ci[bot]]

updates:

• github.com/psf/black: 20.8b1 → 21.8b0
• https://github.com/timothycrosley/isort → https://github.com/PyCQA/isort
• github.com/PyCQA/isort: 5.7.0 → 5.9.3
• github.com/macisamuele/language-formatters-pre-commit-hooks: v1.6.1 → v2.1.0
• 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
• github.com/asottile/blacken-docs: v1.9.1 → v1.11.0
• github.com/asottile/pyupgrade: v2.7.4 → v2.25.0
• github.com/pre-commit/pygrep-hooks: v1.7.0 → v1.9.0