Enable Individual Attendee Collection for RSVP Guests#12

For free RSVPs, only the purchaser’s name/email is collected even when RSVPing for multiple guests. Requesting Individual Attendee Collection to work for RSVPs the same way it already does for paid tickets. (Migrated from featureOS: https://the-events-calendar.featureos.app/p/enable-individual-attendee-collection-for-rsvp-guests)