Draft: Migrate build_image job to buildah
This MR will outline the steps to transition between kaniko and buildah.
Security Notice: GitLab has uncovered a widespread malicious npm supply-chain attack that potentially can destroy user data. All teams are required to audit packages. Further information can be found under the Computer Security Report for November 2025 and the original blog post in https://about.gitlab.com/blog/gitlab-discovers-widespread-npm-supply-chain-attack/
This MR will outline the steps to transition between kaniko and buildah.