Bump css-loader from 2.1.1 to 3.0.0

Bumps [css-loader](https://github.com/webpack-contrib/css-loader) from 2.1.1 to 3.0.0.
- [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/v2.1.1...v3.0.0)

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

package.json

@@ -12,7 +12,7 @@
     "awesome-typescript-loader": "^5.0.0",
     "core-js": "^3.1.3",
     "cross-env": "5.2.0",
-    "css-loader": "2.1.1",
+    "css-loader": "3.0.0",
     "electron": "^5.0.3",
     "electron-builder": "^20.43.0",
     "electron-installer-snap": "^3.2.0",