[pre-commit.ci] pre-commit autoupdate

updates:
- [github.com/asottile/pyupgrade: v2.19.4 → v2.20.0](asottile/pyupgrade@v2.19.4...v2.20.0)

Author: pre-commit-ci[bot]

.pre-commit-config.yaml

@@ -35,7 +35,7 @@ repos:
     -   id: add-trailing-comma
         args: [--py36-plus]
 -   repo: https://github.com/asottile/pyupgrade
-    rev: v2.19.4
+    rev: v2.20.0
     hooks:
     -   id: pyupgrade
         args: [--py36-plus]