Mail templates

[revjtanton]

User Story

As a end-user
I'd like to upload email templates for use by the system
So that I can easily update and manage the templates

Acceptance Criteria

• email njk templates can be uploaded to the API through some means
• the uploaded template is stored by the system in some way (S3)
• the uploaded template can be called by the /send endpoint as a parameter in the body
• the called template is used in the emails sent.

Notes

This may be considered two efforts. Adding the S3 bucket to terraform, and the code to use the S3 bucket. The bucket can be created first and used by the system without the functionality to add new templates to the bucket via the API.