New Navigation breaks Drawer header

What does this MR do and why?

New left sidebar has a sticky header that is covering the right side drawer.

Screenshots or screen recordings

Before	After

How to set up and validate locally

1. enable and switch to new navigation

   Feature.enable(:super_sidebar_nav)

2. setup and enable advanced search
3. Visit the search page http://gdk.test:3000/search
4. Click the syntax options button.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Related to #411402 (closed)