updateWaitingParticipant(id, updates)
The id must correspond to a participant in waitingParticipants() — passing an unknown ID results in an error.
Once access is granted, the participant is removed from waitingParticipants() and a waiting-participant-removed event fires.
Parameters
The session ID of the waiting participant.
Return value
ReturnsPromise<{ id: string }> — resolves with the ID of the updated participant.