⬆ Bump favicons-webpack-plugin from 2.1.0 to 4.2.0

Bumps [favicons-webpack-plugin](https://github.com/jantimon/favicons-webpack-plugin) from 2.1.0 to 4.2.0.
- [Release notes](https://github.com/jantimon/favicons-webpack-plugin/releases)
- [Changelog](https://github.com/jantimon/favicons-webpack-plugin/blob/master/CHANGELOG.md)
- [Commits](jantimon/favicons-webpack-plugin@v2.1.0...v4.2.0)

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

Author: dependabot[bot]

app/package.json

@@ -27,7 +27,7 @@
     "classnames": "^2.2.6",
     "css-loader": "^4.2.2",
     "eslint-plugin-react": "^7.20.6",
-    "favicons-webpack-plugin": "^2",
+    "favicons-webpack-plugin": "^4",
     "fuse.js": "^6.4.1",
     "history": "^5.0.0",
     "html-webpack-plugin": "^3",