if the last sync job is too far in the past (or there was none at all
for now) we run it at the next iteration, so we want to show that
we now calculate the next_run by using either the real last endtime
as time or 0
then in the frontend, we check if the next_run is < now and show 'pending'
(we do it this way also for replication on pve)
Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>