Update pre-commit hook asottile/pyupgrade to v3.21.0 (main) (#8405)

Update pre-commit hook asottile/pyupgrade to v3.21.0

| datasource  | package            | from    | to      |
| ----------- | ------------------ | ------- | ------- |
| github-tags | asottile/pyupgrade | v3.20.0 | v3.21.0 |

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>
Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.pre-commit-config.yaml

@@ -50,7 +50,7 @@ repos:
         args: [--new-from-patch=/tmp/diff.patch]
 
   - repo: https://github.com/asottile/pyupgrade
-    rev: v3.20.0
+    rev: v3.21.0
     hooks:
       - id: pyupgrade