It was possible that join can be executed before conference.init have even started or we haven't reached the point ot create the initialGUMPromise. This was causing the following issues:
- users stuck on the prejoin screen
- participants join 2+ times in the call (we have been creating more than 1 local participants from a single page).
When the prejoin screen is disabled during the prosody login cycle the initial GUM tracks were lost causing the user to start the call without local media and audio/video mute buttons staying forever in pending state.
