Reset user ID's to last free

Is it possible to reset the user IDs to the last available one?
We have had quite a high user fluctuation in the last few months due to the deletion of users, the IDs are quite high.
I’m able to make changes directly in the gitea DB.

It is against most security frameworks to reuse user identifiers. Which begs the question, why do you care about high ID numbers? The ID of any table should be ignored and not used as data.