[pre-commit.ci] pre-commit autoupdate (#657)

updates:
- [github.com/adamchainz/django-upgrade: 1.19.0 → 1.20.0](adamchainz/django-upgrade@1.19.0...1.20.0)

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

.pre-commit-config.yaml

@@ -23,7 +23,7 @@ repos:
     -   id: pyupgrade
         args: [--py38-plus]
   - repo: https://github.com/adamchainz/django-upgrade
-    rev: 1.19.0
+    rev: 1.20.0
     hooks:
     - id: django-upgrade
       args: [--target-version, "3.2"]