* fix(lobby): Inconsistent state after deny and then approve.

Fixes several issues:
- The error on lobby deny is not sticky
- When preJoin is not enabled we were showing conference UI and showing the error, while the participant is denied to enter the meeting.
- There was inconsistent state (after deny we were keeping membersOnly conference state) and when being approved on re-try while being in the meeting, no remote thumbnails are shown although media is flowing.

The scenario is enabling lobby and tryintg to join, denying the first attempt and approving the second one.

* squash: Drop extra hide lobby screen.

* squash: Finish action first before showing the notification.