Bump css-loader from 3.2.1 to 3.4.0

Bumps [css-loader](https://github.com/webpack-contrib/css-loader) from 3.2.1 to 3.4.0.
- [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/v3.2.1...v3.4.0)

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

package.json

@@ -14,7 +14,7 @@
     "awesome-typescript-loader": "^5.0.0",
     "core-js": "^3.4.2",
     "cross-env": "6.0.3",
-    "css-loader": "3.2.1",
+    "css-loader": "3.4.0",
     "electron": "^7.1.7",
     "electron-builder": "22.1.0",
     "electron-download": "^4.1.1",