Private lobbies cannot be invited to on Steam

The old method doesn't work with private match invites as it doesn't have the right security permissions. It's still valid for dedicated servers. It also doesn't work properly with lobbies on VR either, so it needs to be fixed overall.

1. Have two clients that are on Steam and are friends
2. Create a private (but inviteable) listen server match
3. Attempt to send an invite to your friend who also owns the game
4. Notice that the friend gets either no invite or an invite with no data inside of it

Both clients must own Shootergame or Spacewar must be used. Steam will very likely attempt to launch the installed version of the game.