use competitor now introduced in mark passing events instead of relying on a MarkPassing to be in the list

java/com.sap.sailing.server/src/com/sap/sailing/server/impl/RacingEventServiceImpl.java

@@ -833,8 +833,7 @@ public class RacingEventServiceImpl implements RacingEventService, RegattaListen
 
         @Override
         public void markPassingReceived(Competitor competitor, Map<Waypoint, MarkPassing> oldMarkPassings, Iterable<MarkPassing> markPassings) {
-            replicate(new UpdateMarkPassings(getRaceIdentifier(), markPassings.iterator().next().getCompetitor(),
-                    markPassings));
+            replicate(new UpdateMarkPassings(getRaceIdentifier(), competitor, markPassings));
         }
 
         @Override