Add support for multiplatform images
The question is whether we want to build multiplatform images. Kaniko doesn't support building multi-arch images (Docker does).
Some references:
- https://docs.docker.com/build/building/multi-platform/
- https://docs.gitlab.com/ee/ci/docker/using_kaniko.html
- https://blog.siemens.com/2022/07/building-a-multi-arch-container-image-in-unprivileged-containers/
- https://github.com/GoogleContainerTools/kaniko/issues/786
- https://github.com/Jasper-Ben/kaniko/commit/6e021ef6a467aa9665b3cefd8d908d840f05cd1f
- https://github.com/GoogleContainerTools/kaniko/issues/786