documentid: Auth UID
{
email: string,
name: string,
occupation: string | null
}
documentId: gerado automaticamente
{
bannerUrl: string,
date: timestamp,
description: string,
organizer: map -> organizer.email, organizer.name,
organizerId: string,
subscribers: number,
title: string
}
documentId: Auth UID do usuário que está se inscrevendo
{
email: string,
name: string
}