Core/Global: reserve storage for script names vector

(cherry picked from commit c8bf1ab5f7e2e44e37c5affbf69c64917dc45c9e)

src/server/game/Globals/ObjectMgr.cpp

@@ -9158,6 +9158,8 @@ void ObjectMgr::LoadScriptNames()
         return;
     }
 
+    _scriptNamesStore.reserve(result->GetRowCount() + 1);
+
     do
     {
         _scriptNamesStore.push_back((*result)[0].GetString());