Bump css-loader from 0.28.10 to 0.28.11

Bumps [css-loader](https://github.com/webpack-contrib/css-loader) from 0.28.10 to 0.28.11.
- [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@v0.28.10...v0.28.11)

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

package.json

@@ -39,7 +39,7 @@
     "babel-core": "^6.26.0",
     "babel-loader": "^5.4.2",
     "create-react-class": "^15.6.2",
-    "css-loader": "^0.28.10",
+    "css-loader": "^0.28.11",
     "ejs": "^2.3.1",
     "front-matter": "^2.3.0",
     "highlight.js": "^9.5.0",