Set up the service monitoring for the log migration script. Add a database migration to add the logs_archived column.

workers/buildlogsarchiver.py

@@ -16,7 +16,7 @@ POLL_PERIOD_SECONDS = 30
 logger = logging.getLogger(__name__)
 sched = BlockingScheduler()
 
-@sched.scheduled_job(trigger='interval', seconds=1)
+@sched.scheduled_job(trigger='interval', seconds=30)
 def archive_redis_buildlogs():
   """ Archive a single build, choosing a candidate at random. This process must be idempotent to
       avoid needing two-phase commit. """