[pre-commit.ci] pre-commit autoupdate

updates:
- [github.com/PyCQA/isort: 5.8.0 → 5.9.3](PyCQA/isort@5.8.0...5.9.3)
- [github.com/psf/black: 21.5b2 → 21.9b0](psf/black@21.5b2...21.9b0)
- [github.com/asottile/pyupgrade: v2.19.0 → v2.28.0](asottile/pyupgrade@v2.19.0...v2.28.0)

.pre-commit-config.yaml

@@ -21,15 +21,15 @@ repos:
       - id: autoflake
         args: ["--in-place", "--remove-all-unused-imports"]
   - repo: https://github.com/PyCQA/isort
-    rev: 5.8.0
+    rev: 5.9.3
     hooks:
       - id: isort
   - repo: https://github.com/psf/black
-    rev: 21.5b2
+    rev: 21.9b0
     hooks:
       - id: black
   - repo: https://github.com/asottile/pyupgrade
-    rev: v2.19.0
+    rev: v2.28.0
     hooks:
       - id: pyupgrade
         args: [--py37-plus]