Set show prop for OutlinePane stories (#10336)

GitOrigin-RevId: 621b5d1ba9e4f67beb53efc73eb0c2925c1a9df4

services/web/frontend/stories/outline.stories.js

@@ -56,6 +56,7 @@ export default {
     outline: [],
     jumpToLine: () => {},
     onToggle: () => {},
+    show: true,
   },
   decorators: [ScopeDecorator],
 }