ConstructBakeFile constructs a docker-bake.json to be passed to `docker buildx bake`.

RunCommand runs a command for the repo, with standard environment variables set.

RunCrane builds docker images using go-containerregistry, rather than relying on Docker.

RunDocker builds docker images using the `docker buildx bake` commands.

RunMake runs a make command for the repo, with standard environment variables set.

RunSave handles the --save portion.

VerboseCommand runs a command, outputting stderr and stdout.

Define variants, which control the base image of an image.

Define variants, which control the base image of an image.

Define variants, which control the base image of an image.

PrimaryVariant is the variant that DefaultVariant actually builds.

Types mirrored from https://github.com/docker/buildx/blob/master/bake/bake.go.