Host does not receive a notification when someone RSVPs to their event

## Steps to Reproduce 1. Create an event as a host 2. Have another user RSVP to the event ## Expected The event host receives a notification (in-app and/or email) that someone has RSVPed to their event. ## Actual No notification is sent to the host. The host has no way of knowing someone RSVPed unless they manually check the event attendance list.