Implement guest access mode in dashboard meeting settings

Summary

The guest access mode will allow the organizer to configure access to a meeting for guests and invited users.

The organizer needs to configure:

• If guests are allowed (on by default)
• If guests have to enter through the waiting room

The UI mockup can be found in the product ticket.

The dashboard uses the API defined in the controller ticket.

If Enable very high level of protection is enabled, the *guest access switch as well as the guest access mode dropdown elements are not shown in the dashboard. This might require moving the Enable very high level of protection above the other ui elements in order to avoid them being moved up and down when turning the feature on and off.