New parameter available, wait_for_deployment. Default value is true. Controls whether the action waits for the deployment to be complete or whether it just starts it in AWS and then exits. Deployments, especially immutable ones can take a long time to complete and eat up a lot of GitHub Actions minutes. So if you prefer
to just start the deployment in Elastic Beanstalk and not wait for it to be completely finished then you can set this parameter to false. Thanks to @kceb for the idea.