[pre-commit.ci] pre-commit autoupdate

updates:
- https://github.com/ambv/black → https://github.com/psf/black
- [github.com/psf/black: 20.8b1 → 21.9b0](psf/black@20.8b1...21.9b0)
- [github.com/pre-commit/pre-commit-hooks: v3.2.0 → v4.0.1](pre-commit/pre-commit-hooks@v3.2.0...v4.0.1)
- [github.com/PyCQA/isort: 5.6.3 → 5.9.3](PyCQA/isort@5.6.3...5.9.3)
- https://gitlab.com/pycqa/flake8 → https://github.com/PyCQA/flake8
- [github.com/PyCQA/flake8: 3.8.4 → 4.0.1](PyCQA/flake8@3.8.4...4.0.1)

Author: pre-commit-ci[bot]

.pre-commit-config.yaml

@@ -1,11 +1,11 @@
 repos:
-  - repo: https://github.com/ambv/black
-    rev: 20.8b1
+  - repo: https://github.com/psf/black
+    rev: 21.9b0
     hooks:
       - id: black
         exclude: ^(oauth2_provider/migrations/|tests/migrations/)
   - repo: https://github.com/pre-commit/pre-commit-hooks
-    rev: v3.2.0
+    rev: v4.0.1
     hooks:
       - id: check-ast
       - id: trailing-whitespace
@@ -16,12 +16,12 @@ repos:
       - id: mixed-line-ending
         args: ['--fix=lf']
   - repo: https://github.com/PyCQA/isort
-    rev: 5.6.3
+    rev: 5.9.3
     hooks:
       - id: isort
         exclude: ^(oauth2_provider/migrations/|tests/migrations/)
-  - repo: https://gitlab.com/pycqa/flake8
-    rev: 3.8.4
+  - repo: https://github.com/PyCQA/flake8
+    rev: 4.0.1
     hooks:
       - id: flake8
         exclude: ^(oauth2_provider/migrations/|tests/migrations/)