Cornerstone content panel misses collapsible container

[afercia]

On current trunk: looks like the Cornerstone content panel in the sidebar misses some padding:

As far as I can tell, the collapsibles content should be wrapped within a Collapsible__Content container which is missing.

[afercia]

Looks like this should use the SidebarCollapsible component, also in the meta box:

See

wordpress-seo/js/src/components/CollapsibleCornerstone.js

Line 10 in af9c1b2

import Collapsible from "./SidebarCollapsible";