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

@@ -56,7 +56,7 @@
     "prettier": "3.5.3",
     "sass": "^1.89.2",
     "style-dictionary": "3.9.2",
-    "stylelint": "16.20.0",
+    "stylelint": "16.21.0",
     "stylelint-config-standard-scss": "^15.0.1",
     "validate-branch-name": "^1.3.2",
     "xo": "^1.1.0"