Hide Fake Section 2 in XB and replace with Olivero section

Problem/Motivation

Follow-up to 🐛 Mark the XB components as experimental, not stable Active

Maybe this should be two issues but just making one for now. I'm not sure if we can create an Olivero one as when I created sections before it was in the XB codebase. That may have changed.

It doesn't look good that we have the Fake Section 2 part and the text above it.

Steps to reproduce

Proposed resolution

Remove the Fake Section 2 and supporting text.

TBD: If it's empty, we probably need some other text? Or can we add an Olivero section?

Remaining tasks

TBD

User interface changes

The user will not see a "Fake Section 2" and its supporting text in the XB sections.

API changes

Data model changes