Hot join a room at floor 9 will halt the game

Symptom:

(0.10.9-1370) If a player joins a hot join room while the game is at floor 9 (final boss). Boss behavior will pause and cannot continue.

Cause:

Final boss will halt and wait for everyone to generate each minigame stage (orbs), which in this case is not possible for new player who is just in the town loadout screen.

The only way to get from this dead lock is to kick this new player or have him leave, boss stage will be then able to continue to play normally.

Potential fix:

- Exclude non-playing players from minigame generation waiting list. The only downside is when that player actually jumps into the play stage in the middle of minigame, he will find non-exist or broken stage.