Bump css-loader from 3.3.0 to 3.4.0

Bumps [css-loader](https://github.com/webpack-contrib/css-loader) from 3.3.0 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](webpack-contrib/css-loader@v3.3.0...v3.4.0)

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

package.json

@@ -26,7 +26,7 @@
     "@babel/preset-env": "^7.7.7",
     "babel-eslint": "^10.0.3",
     "babel-loader": "^8.0.6",
-    "css-loader": "^3.3.0",
+    "css-loader": "^3.4.0",
     "eslint": "^6.8.0",
     "eslint-config-standard": "^14.1.0",
     "eslint-import-resolver-webpack": "^0.12.0",