fix: remove graph when selecting unreachable server

        public static void ShowWindowFromWorldStorageWindow(WorldStorageServer server, WorldStorageUser user)

        {

            var window = GetWindow<WorldGraphWindow>("Graph Editor", true, typeof(SceneView));

            if (window.myGraph != null && window.myGraph.ServerAndLocalDifferent() && EditorUtility.DisplayDialog("Saving node positions", "The World Graph has been modified. \nWould you like to push the modifications to the server ?", "Yes", "No"))

            if (window.myGraph != null)

            {

                if (window.myGraph.ServerAndLocalDifferent() && EditorUtility.DisplayDialog("Saving node positions", "The World Graph has been modified. \nWould you like to push the modifications to the server ?", "Yes", "No"))

                {

                    window.myGraph.SaveInServer();

                }

                window.rootVisualElement.Remove(window.myGraph);

            }

            GraphEditorWindow.ResetWindow();

            window.worldStorageServer = server;

            window.worldStorageUser = user;