Bump webpack-dev-server from 2.11.5 to 4.13.3

Bumps [webpack-dev-server](https://github.com/webpack/webpack-dev-server) from 2.11.5 to 4.13.3.
- [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/commits/v4.13.3)

---
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>

Author: dependabot[bot]

package.json

@@ -67,7 +67,7 @@
     "rimraf": "^2.6.2",
     "style-loader": "^0.19.0",
     "webpack": "^3.8.1",
-    "webpack-dev-server": "^2.9.4"
+    "webpack-dev-server": "^4.13.3"
   },
   "dependencies": {
     "@azure/storage-blob": "^10.5.0",