auto-deploy docker image to public ECR repo when main is released

[elrayle]

Description

When a release is created from the main branch, the docker image should be created and pushed to the public ECR repo with tag latest.

Tasks

• create public repo with name ld4p/qa_authority_lookup
• create github action that builds the docker image and deploys it to the public repo when a release is created from the main branch
• update instructions to describe how to use this image
• if needed, update AWS templates
• update our deploy process to use the latest image in the public repo

Related Work

PR #29 - autodeploy docker image to ECR repository through github actions (on push to dev)