Change SyncSeatLinkWorker cron job execution time

What does this MR do?

Part of #326114

Change time of scheduled cron job to sync seat links. The execution of the seat link sync has to be timed after the cron job in CustomersDot for reconciliations was executed. That job is scheduled at midnight (code).

To ensure that the execution time of the seat link sync is after the one in CustomersDot, the timezone is explicitly set to UTC. As well as slightly delayed to have some buffer for processing time.

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