Bump webpack-dev-server from 3.11.3 to 4.15.1

Bumps [webpack-dev-server](https://github.com/webpack/webpack-dev-server) from 3.11.3 to 4.15.1.
- [Release notes](https://github.com/webpack/webpack-dev-server/releases)
- [Changelog](https://github.com/webpack/webpack-dev-server/blob/master/CHANGELOG.md)
- [Commits](https://github.com/webpack/webpack-dev-server/compare/v3.11.3...v4.15.1)

---
updated-dependencies:
- dependency-name: webpack-dev-server
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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

package.json

@@ -160,7 +160,7 @@
     "react-test-renderer": "^16.14.0",
     "stylelint": "^14.16.1",
     "stylelint-config-standard-scss": "^6.1.0",
-    "webpack-dev-server": "^3.11.3",
+    "webpack-dev-server": "^4.15.1",
     "yargs": "^17.6.2"
   },
   "resolutions": {