Let world shutdown dz early for empty expeditions

Since world now tracks empty expeditions it can determine when to
shutdown dynamic zone instances when the rule is enabled rather than
letting zones do it.

zone/worldserver.cpp

@@ -2915,6 +2915,7 @@ void WorldServer::HandleMessage(uint16 opcode, const EQ::Net::Packet &p)
 	case ServerOP_ExpeditionDzCompass:
 	case ServerOP_ExpeditionDzSafeReturn:
 	case ServerOP_ExpeditionDzZoneIn:
+	case ServerOP_ExpeditionDzDuration:
 	case ServerOP_ExpeditionRemoveCharLockouts:
 	{
 		Expedition::HandleWorldMessage(pack);