Don't auto-merge storybook renovate PR's (#1887)

Author: calebeby

.renovaterc.json

@@ -7,6 +7,14 @@
       "packageNames": ["node"],
       "enabled": false
     },
+    {
+      "matchPackagePatterns": ["storybook"],
+      "automerge": false,
+      "prBodyNotes": [
+        ":warning: **Warning:** There are likely to be breaking changes, please closely review the pattern library preview."
+      ],
+      "commitMessagePrefix": "[Review carefully]"
+    },
     {
       "packageNames": ["@wordpress/block-library"],
       "extends": ["schedule:monthly"],