Core/Transports: Fixed crash happening during teleporting transports

Closes #11793

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

@@ -13555,12 +13555,7 @@ void Unit::CleanupsBeforeDelete(bool finalCleanup)
 {
     CleanupBeforeRemoveFromMap(finalCleanup);
 
-    if (GetTransport())
-    {
-        GetTransport()->RemovePassenger(this);
-        SetTransport(NULL);
-        m_movementInfo.transport.Reset();
-    }
+    WorldObject::CleanupsBeforeDelete(finalCleanup);
 }
 
 void Unit::UpdateCharmAI()