Java Spring Boot: Offline download

Add the published binary to the offline download template at https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/ci/templates/Security/Secure-Binaries.gitlab-ci.yml

More information about the process at https://docs.gitlab.com/ee/user/application_security/offline_deployments/#loading-docker-images-onto-your-offline-host

The template currently only supports pulling and pushing images to/from from the container registry; it will need to be extended to also work with the package repository. The documentation will also need to be updated, since it only references docker images.

Edited by David Nelson