Enable traversal_ids for all project search queries

What does this MR do and why?

Related to gitlab-com/gl-infra/production#17429 (closed)

The FF has been enabled on production without issue for a bit so I'm removing the flag

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

N/A

How to set up and validate locally

1. setup gdk for elasticsearch
2. enable the performance bar
3. perform a group searches for projects

• http://gdk.test:3000/search?search=project&group_id=24&scope=projects

1. verify that the Elasticsearch queries use traversal_ids in the query

[ { "prefix": { "traversal_ids": { "_name": "project:ancestry_filter:descendants", "value": "24-" } } } ] } } ] } }