Bump css-loader from 4.2.1 to 5.0.1

Bumps [css-loader](https://github.com/webpack-contrib/css-loader) from 4.2.1 to 5.0.1.
- [Release notes](https://github.com/webpack-contrib/css-loader/releases)
- [Changelog](https://github.com/webpack-contrib/css-loader/blob/master/CHANGELOG.md)
- [Commits](https://github.com/webpack-contrib/css-loader/compare/v4.2.1...v5.0.1)

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

package.json

@@ -30,7 +30,7 @@
     "bluebird": "^3.7.2",
     "bulma": "^0.9.0",
     "co": "~4.6.0",
-    "css-loader": "^4.2.1",
+    "css-loader": "^5.0.1",
     "debug": "^4.1.1",
     "ejs": "^3.1.3",
     "file-loader": "^6.0.0",