Set default guest configuration

Changes to the current (v2.2) default configuration of the guest feature.

The ideal is to keep the simplified guest feature as default (`authenticatedGuests=false`)
but we also need to be in sync with Greenlight settings to make this happen.

Greenlight will have to re-add the `guest=true` param on user's join API call when ASK_MODERATOR
is set as guest's policy.