Bump autoprefixer from 10.4.19 to 10.4.21

Bumps [autoprefixer](https://github.com/postcss/autoprefixer) from 10.4.19 to 10.4.21.
- [Release notes](https://github.com/postcss/autoprefixer/releases)
- [Changelog](https://github.com/postcss/autoprefixer/blob/main/CHANGELOG.md)
- [Commits](postcss/autoprefixer@10.4.19...10.4.21)

---
updated-dependencies:
- dependency-name: autoprefixer
  dependency-version: 10.4.21
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

package.json

@@ -34,7 +34,7 @@
     "@babel/preset-env": "^7.25.8",
     "@typescript-eslint/eslint-plugin": "^7.18.0",
     "@typescript-eslint/parser": "^7.18.0",
-    "autoprefixer": "^10.4.19",
+    "autoprefixer": "^10.4.21",
     "concurrently": "^9.0.1",
     "del": "^7.1.0",
     "eslint": "^8.57.0",