[pre-commit.ci] pre-commit autoupdate

updates:
- [github.com/jackdewinter/pymarkdown: v0.9.15 → v0.9.21](jackdewinter/pymarkdown@v0.9.15...v0.9.21)
- [github.com/adamchainz/django-upgrade: 1.19.0 → 1.20.0](adamchainz/django-upgrade@1.19.0...1.20.0)

.pre-commit-config.yaml

@@ -12,7 +12,7 @@ repos:
     hooks:
       - id: flake8
   - repo: https://github.com/jackdewinter/pymarkdown
-    rev: v0.9.15
+    rev: v0.9.21
     hooks:
       - id: pymarkdown
         args:
@@ -24,7 +24,7 @@ repos:
     hooks:
     -   id: pyupgrade
   - repo: https://github.com/adamchainz/django-upgrade
-    rev: "1.19.0"  # replace with latest tag on GitHub
+    rev: "1.20.0"  # replace with latest tag on GitHub
     hooks:
     -   id: django-upgrade
         args: [--target-version, "5.0"]   # Replace with Django version