chore: set started_at when updating meeting

Author: wagner-wutzke

src/main/java/net/nordeck/ovc/backend/service/MeetingServiceImpl.java

@@ -594,6 +594,7 @@ private MeetingEntity updateDataAndSave(MeetingUpdateDTO newDTO, MeetingEntity e
         existing.setName(newDTO.getName());
         existing.setLobbyEnabled(newDTO.isLobbyEnabled());
         existing.setUpdatedAt(ZonedDateTime.now());
+        existing.setStartedAt(newDTO.getStartedAt());
 
         // update recurrence data only for parent meeting, for children, we need to recreate them
         if (existing.isRecurrentParent())