JobCleaner context deadline

[PumpkinSeed]

Problem

JobCleaner runOnce has a strict deadline which 30*time.Second, that would be nice to set it dynamically.

Reason

We got a bigger load in our queue, which was 15.000.000 job per day and our cleanup process removes the completed jobs after 3 day. But the actual cleanup always failed because of this context deadline which resulted performance issues, because other queries of the riverqueue started to slow down since the cleanup process never succeed. We have time to complete this task so it would be nice to set this context deadline.