Add "refresh-participant-list" for participants in a room just deleted
Add "refresh-participant-list" for participants in a room just deleted

Note, however, that the participant will never receive that message from
the signaling endpoint, but a 404 error due to the room no longer
existing. In any case, this ends the pending signaling request as soon
as the room is deleted instead of keep waiting until the timeout ends.

Signed-off-by: Daniel Calviño Sánchez <bd7629e975cc0e00ea7cda4ab6a120f2ee42ac1b@gmail.com>

nextcloud/spreed,nextcloud/spreed,nextcloud/spreed