Update stylelint from 9.8.0 to 9.9.0

Author: dependencies-bot

packages/generator/app/templates/package.json

@@ -67,7 +67,7 @@
     "react-test-renderer": "16.6.3",
     "sinon": "7.1.1",
     "sinon-chai": "3.3.0",
-    "stylelint": "9.8.0",
+    "stylelint": "9.9.0",
     "xvfb-maybe": "0.2.1",
     "yo": "2.0.5"
   },