Workflow is used to publish a Docker image to docker hub on release.

The docker hub URL: https://hub.docker.com/r/drydockcloud/ci-phpcs

We use an access token that is created by member who has access to docker hub and the username and password is added to GitHub as a repository secret. Names are DOCKER_USERNAME and DOCKER_PASSWORD respectively.

• https://docs.github.com/en/actions/publishing-packages/publishing-docker-images#publishing-images-to-docker-hub