chore(package): update stylelint to version 13.1.0

Closes #212

Author: greenkeeper[bot]

package.json

@@ -32,7 +32,7 @@
     "offline-plugin": "^4.9.0",
     "properties-loader": "0.0.1",
     "style-loader": "^0.20.1",
-    "stylelint": "^9.0.0",
+    "stylelint": "^13.1.0",
     "stylelint-config-standard": "^18.0.0",
     "stylelint-no-unsupported-browser-features": "^2.0.0",
     "transifex-loader": "^5.0.0",