Misc: Pass std::chrono types by value everywhere.

src/server/game/Entities/GameObject/GameObject.cpp

@@ -801,7 +801,7 @@ void GameObject::AddUniqueUse(Player* player)
     m_unique_users.insert(player->GetGUID());
 }
 
-void GameObject::DespawnOrUnsummon(Milliseconds const& delay, Seconds const& forceRespawnTime)
+void GameObject::DespawnOrUnsummon(Milliseconds delay, Seconds forceRespawnTime)
 {
     if (delay > 0ms)
     {