chore(deps-dev): Bump stylelint from 16.20.0 to 16.21.0

Bumps [stylelint](https://github.com/stylelint/stylelint) from 16.20.0 to 16.21.0.
- [Release notes](https://github.com/stylelint/stylelint/releases)
- [Changelog](https://github.com/stylelint/stylelint/blob/main/CHANGELOG.md)
- [Commits](stylelint/stylelint@16.20.0...16.21.0)

---
updated-dependencies:
- dependency-name: stylelint
  dependency-version: 16.21.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

package-lock.json

@@ -90,7 +90,7 @@
     "gettext-parser": "^8.0.0",
     "happy-dom": "^17.6.3",
     "sass": "^1.89.2",
-    "stylelint": "^16.20.0",
+    "stylelint": "^16.21.0",
     "tslib": "^2.8.1",
     "typedoc": "^0.28.5",
     "typedoc-plugin-missing-exports": "^4.0.0",