Core/Vmaps: Fixed use after free and deadlocks when loading a model file fails

Port From (https://github.com/TrinityCore/TrinityCore/commit/d05dbaaecbd4bf7e1c0fd32d0fef34341b4067f6)

Source/Game/Collision/Models/WorldModel.cs

@@ -331,7 +331,6 @@ namespace Game.Collision
         uint RootWMOID;
         List<GroupModel> groupModels = new();
         BIH groupTree = new();
-        string name;    // valid only while model is held in VMapManager2::iLoadedModelFiles
 
         public override bool IntersectRay(Ray ray, ref float distance, bool stopAtFirstHit, ModelIgnoreFlags ignoreFlags)
         {
@@ -423,9 +422,6 @@ namespace Game.Collision
             return groupTree.ReadFromFile(reader);
         }
 
-        public string GetName() { return name; }
-        public void SetName(string newName) { name = newName; }
-
         public bool IsM2() { return Flags.HasFlag(ModelFlags.IsM2); }
     }