chore: bump autoprefixer in /examples/openfeature_web/webapp

Bumps [autoprefixer](https://github.com/postcss/autoprefixer) from 10.4.20 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@10.4.20...10.4.21)

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

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

examples/openfeature_web/webapp/package-lock.json

@@ -32,7 +32,7 @@
   "devDependencies": {
     "@babel/eslint-parser": "^7.26.8",
     "@babel/preset-env": "^7.26.9",
-    "autoprefixer": "^10.4.20",
+    "autoprefixer": "^10.4.21",
     "babel-loader": "^10.0.0",
     "babel-plugin-transform-class-properties": "^6.24.1",
     "babel-preset-env": "^1.7.0",