Resolve "Remove replace_order_by_created_at_with_id feature flag"

What does this MR do and why?

With successful resolution of the bug we can remove the replace_order_by_created_at_with_id feature flag.

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.

Closes #364616 (closed), #360757 (closed)