Ci::BuildTraceChunkFlushWorker should be high urgency

As a corrective action for https://app.incident.io/gitlab/incidents/184 this job current runs on catchall, and is a dependency for Ci::UpdateBuildStateService which blocked pipelines from completing.

Catchall should only be used for jobs that don't have time constraints so we should re-categorize this job for higher urgency.

This ticket was created from INC-184 and was automatically exported by incident.io 🔥