Bump the frontend group with 2 updates

Bumps the frontend group with 2 updates: [postcss](https://github.com/postcss/postcss) and [stylelint](https://github.com/stylelint/stylelint).


Updates `postcss` from 8.4.41 to 8.4.42
- [Release notes](https://github.com/postcss/postcss/releases)
- [Changelog](https://github.com/postcss/postcss/blob/main/CHANGELOG.md)
- [Commits](postcss/postcss@8.4.41...8.4.42)

Updates `stylelint` from 16.8.2 to 16.9.0
- [Release notes](https://github.com/stylelint/stylelint/releases)
- [Changelog](https://github.com/stylelint/stylelint/blob/main/CHANGELOG.md)
- [Commits](stylelint/stylelint@16.8.2...16.9.0)

---
updated-dependencies:
- dependency-name: postcss
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: frontend
- dependency-name: stylelint
  dependency-type: direct:development
  update-type: version-update:semver-minor
  dependency-group: frontend
...

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -20,10 +20,10 @@
     "@double-great/stylelint-a11y": "3.0.2",
     "autoprefixer": "10.4.20",
     "cssnano": "7.0.5",
-    "postcss": "8.4.41",
+    "postcss": "8.4.42",
     "postcss-cli": "11.0.0",
     "prettier": "3.3.3",
-    "stylelint": "16.8.2",
+    "stylelint": "16.9.0",
     "stylelint-config-standard": "36.0.1"
   }
 }