Update eslint-config-stylelint to the latest version 🚀 (#40)

## The devDependency [eslint-config-stylelint](https://github.com/stylelint/eslint-config-stylelint) was updated from `10.0.0` to `11.0.0`.
This version is **not covered** by your **current version range**.

If you don’t accept this pull request, your project will work just like it did before. However, you might be missing out on a bunch of new features, fixes and/or performance improvements from the dependency update.

---

[Find out more about this release](https://github.com/stylelint/eslint-config-stylelint).

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Author: greenkeeper[bot]

package.json

@@ -19,7 +19,7 @@
   ],
   "devDependencies": {
     "eslint": "^5.0.0",
-    "eslint-config-stylelint": "^10.0.0",
+    "eslint-config-stylelint": "^11.0.0",
     "jest": "^23.4.1",
     "jest-preset-stylelint": "^1.3.0",
     "npm-run-all": "^4.1.5",