BE/AWS: Email notifications with SES

See the design doc here: https://www.notion.so/generate-nu/Prisere-Disaster-Notification-System-279f18dd5a9480b2b5e3e799f189d5de?source=copy_link

We want to take the next step for AWS integration with notifications, which is setting up SES in AWS to send out the emails that have been created as part of the FEMA import and notifications that have not been acknowledged yet in the DB