Fix search helper vertical navigation json method

What does this MR do and why?

The condition on the vertical navigation JSON generator had minor logical issues.

4/7 add vertical navigation vue app

• Search Page vertical navigation search helper (merged)
• Search Page layout changes (merged)
• Move filters into their own component (merged)
• Fix search helper vertical navigation JSON method (merged) 👈 this MR
• Search Page Vue vertical navigation (merged)
  • Fix missing feature flag check in Vue vertical menu (merged)
  • Convert all Search Page RSpecs to support vertical search navigation

Screenshots or screen recordings

This is a technical depth change there are no visual changes.

How to set up and validate locally

1. checkout this branch
2. In the rails console enable the feature flag

   Feature.enable(:search_page_vertical_nav)

3. disable "search with Elasticsearch enabled" (http://127.0.0.1:3000/admin/application_settings/advanced_search)
   
4. search any term on the search page http://127.0.0.1:3000/search
5. code search should not appear

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 #293740 (closed)