Bump css-loader from 3.2.0 to 3.4.0 in /js

Bumps [css-loader](https://github.com/webpack-contrib/css-loader) from 3.2.0 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/v3.2.0...v3.4.0)

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

js/package.json

@@ -31,7 +31,7 @@
     "@babel/polyfill": "^7.7.0",
     "@babel/preset-env": "^7.7.6",
     "babel-loader": "^8.0.6",
-    "css-loader": "^3.3.2",
+    "css-loader": "^3.4.0",
     "karma": "^4.4.1",
     "mini-css-extract-plugin": "^0.8.0",
     "style-loader": "^1.0.1",