Core/Players: Fixed tabard championing in normal modes of WotLK level 80 dungeons

Closes #9227

src/server/game/Entities/Unit/Unit.cpp

@@ -2209,7 +2209,7 @@ void Unit::SendMeleeAttackStop(Unit* victim)
 {
     WorldPacket data(SMSG_ATTACKSTOP, (8+8+4));
     data.append(GetPackGUID());
-    data.append(victim ? victim->GetPackGUID() : 0);
+    data.appendPackGUID(victim ? victim->GetGUID() : 0);
     data << uint32(0);                                     //! Can also take the value 0x01, which seems related to updating rotation
     SendMessageToSet(&data, true);
     sLog->outDebug(LOG_FILTER_UNITS, "WORLD: Sent SMSG_ATTACKSTOP");