Remove `if defined?(wait_for_less_busy_worker)` after Puma 5 upgrade is finished
To have a more convenient upgrade from our Puma fork to the upstream version of Puma 5, we needed to introduce if defined?(wait_for_less_busy_worker)
check in Puma configs (see !48897 (comment 464478926)).
This is done for compatibility with the older version which didn't have this setting and the fact we need to update .com and self-managed.
After the upgrade is done and we're sure everything works as expected, we need to drop this condition.
It should be done it:
- GitLab repo: !61572 (merged)
- Omnibus repo: omnibus-gitlab!5245 (merged)
- CNG repo: gitlab-org/build/CNG!662 (merged)
- GDK repo: not needed
Edited by Aleksei Lipniagov