Lobby gamelist not updated correctly when a player leaves or joins a match.

[user1]

When a player leaves or joins a match in the multiplayer lobby, the game is not updated correctly in the game list. It will show the previous player assignments and not display the correct player assignments until some other game setting is changed.

[user1]

In ​24686:

Fix lobby gamelist issues when clients join and leave a match.

Accepted By: wraitii

Fixes: ​#5929, ​#5933

Differential Revision: ​https://code.wildfiregames.com/D3406