Bump @wordpress/stylelint-config from 21.20.0 to 21.24.0 (#352)

Bumps [@wordpress/stylelint-config](https://github.com/WordPress/gutenberg/tree/HEAD/packages/stylelint-config) from 21.20.0 to 21.24.0.
- [Release notes](https://github.com/WordPress/gutenberg/releases)
- [Changelog](https://github.com/WordPress/gutenberg/blob/trunk/packages/stylelint-config/CHANGELOG.md)
- [Commits](https://github.com/WordPress/gutenberg/commits/@wordpress/[email protected]/packages/stylelint-config)

---
updated-dependencies:
- dependency-name: "@wordpress/stylelint-config"
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

package.json

@@ -53,7 +53,7 @@
     "@wordpress/dependency-extraction-webpack-plugin": "^4.24.0",
     "@wordpress/env": "^8.3.0",
     "@wordpress/eslint-plugin": "^15.1.0",
-    "@wordpress/stylelint-config": "^21.20.0",
+    "@wordpress/stylelint-config": "^21.24.0",
     "archiver": "^5.3.1",
     "babel": "^6.23.0",
     "babel-loader": "^9.1.3",