Warn developers when changing settings IA without updating search

Proposal

When any team adds a new settings section (or page with sections), this search feature wouldn't auto-know about it, but we have to manually update it. To some extend, we can probably solve this with documentation. But we should also consider adding some Danger detection in CI (similiar to the message that you get today if you touch a line of haml that contains a data-test-id) to catch cases where someone adds a new section.

Implementation plan

• Use Danger to detect new settings section HTML in the changed lines of an MR. This can probably be done very similar to danger/qa_selector/Dangerfile.
• For the matching pattern(s), we have to consider that it could be:
  • in a Haml file as plain CSS classes
  • in a Haml file, using the Layouts::SettingsBlockComponent ViewComponent
  • in a Vue template