[pre-commit.ci] pre-commit autoupdate

updates:
- [github.com/psf/black: 21.5b1 → 21.6b0](psf/black@21.5b1...21.6b0)
- [github.com/PyCQA/isort: 5.8.0 → 5.9.1](PyCQA/isort@5.8.0...5.9.1)
- [github.com/asottile/pyupgrade: v2.18.1 → v2.19.4](asottile/pyupgrade@v2.18.1...v2.19.4)

.pre-commit-config.yaml

@@ -33,16 +33,16 @@ repos:
   - id: trailing-whitespace
 
 - repo: https://github.com/psf/black
-  rev: 21.5b1
+  rev: 21.6b0
   hooks:
   - id: black
 
 - repo: https://github.com/PyCQA/isort
-  rev: 5.8.0
+  rev: 5.9.1
   hooks:
   - id: isort
 
 - repo: https://github.com/asottile/pyupgrade
-  rev: v2.18.1
+  rev: v2.19.4
   hooks:
   - id: pyupgrade