[pre-commit.ci] pre-commit autoupdate

updates:
- [github.com/asottile/pyupgrade: v2.13.0 → v2.14.0](https://github.com/asottile/pyupgrade/compare/v2.13.0...v2.14.0)
- [github.com/psf/black: 21.4b0 → 21.4b2](https://github.com/psf/black/compare/21.4b0...21.4b2)

.pre-commit-config.yaml

 repos:
   - repo: https://github.com/asottile/pyupgrade
-    rev: v2.13.0
+    rev: v2.14.0
     hooks:
       - id: pyupgrade
         args: ["--py36-plus"]
@@ -12,7 +12,7 @@ repos:
         files: "^(?!examples/)"
         args: ["--application-directories", "src"]
   - repo: https://github.com/psf/black
-    rev: 21.4b0
+    rev: 21.4b2
     hooks:
       - id: black
   - repo: https://github.com/PyCQA/flake8