Bump webpack-cli from 3.3.12 to 4.0.0

Bumps [webpack-cli](https://github.com/webpack/webpack-cli) from 3.3.12 to 4.0.0.
- [Release notes](https://github.com/webpack/webpack-cli/releases)
- [Changelog](https://github.com/webpack/webpack-cli/blob/master/CHANGELOG.md)
- [Commits](https://github.com/webpack/webpack-cli/compare/v3.3.12...webpack-cli@4.0.0)

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

package.json

@@ -50,6 +50,6 @@
         "ts-loader": "^8.0.4",
         "typescript": "^4.0.3",
         "webpack": "^4.44.2",
-        "webpack-cli": "^3.3.12"
+        "webpack-cli": "^4.0.0"
     }
 }