[pre-commit.ci] pre-commit autoupdate

updates:
- [github.com/psf/black: 21.7b0 → 21.8b0](psf/black@21.7b0...21.8b0)
- [github.com/asottile/pyupgrade: v2.24.0 → v2.25.0](asottile/pyupgrade@v2.24.0...v2.25.0)

Author: pre-commit-ci[bot]

.pre-commit-config.yaml

@@ -1,6 +1,6 @@
 repos:
 -   repo: https://github.com/psf/black
-    rev: 21.7b0
+    rev: 21.8b0
     hooks:
     - id: black
       args: [--safe, --quiet]
@@ -21,7 +21,7 @@ repos:
     hooks:
     -   id: flake8
 -   repo: https://github.com/asottile/pyupgrade
-    rev: v2.24.0
+    rev: v2.25.0
     hooks:
     - id: pyupgrade
       args: [--py36-plus]