Bump webpack-dev-server from 2.9.4 to 3.1.11

Bumps [webpack-dev-server](https://github.com/webpack/webpack-dev-server) from 2.9.4 to 3.1.11.
- [Release notes](https://github.com/webpack/webpack-dev-server/releases)
- [Changelog](https://github.com/webpack/webpack-dev-server/blob/master/CHANGELOG.md)
- [Commits](webpack/webpack-dev-server@v2.9.4...v3.1.11)

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

Author: dependabot[bot]

package.json

@@ -22,7 +22,7 @@
 		"url-loader": "^0.6.2",
 		"webpack": "^3.6.0",
 		"webpack-archive-plugin": "^3.0.0",
-		"webpack-dev-server": "^2.9.1"
+		"webpack-dev-server": "^3.1.11"
 	},
 	"scripts": {
 		"lint": "eslint src test",