Fix initial backup created_at argument
diff --git a/staffeln/conductor/backup.py b/staffeln/conductor/backup.py
index f78f90d..7b226d4 100755
--- a/staffeln/conductor/backup.py
+++ b/staffeln/conductor/backup.py
@@ -536,6 +536,7 @@
                 instance_id=task.instance_id,
                 backup_completed=1,
                 incremental=task.incremental,
+                created_at=datetime.now(),
             )
         )
         task.backup_status = constants.BACKUP_COMPLETED