//Handler for the signout button.
 public void OnSignoutClicked()
 {
     if (RaceManager.Instance != null)
     {
         RaceManager.Instance.CleanUp();
     }
     Debug.Log("Signing out...");
     if (PlayGamesPlatform.Instance != null)
     {
         PlayGamesPlatform.Instance.SignOut();
     }
     else
     {
         Debug.Log("PG Instance is null!");
     }
     NavigationUtil.ShowGameMenu();
 }