Perhaps image.yaml should be a RHEL8-based container, not a legacy one.

[jmtd]

Discussion in #58 got me thinking whether it makes sense for the oldest (now deprecated) RHEL7-based image should be image.yaml, the default target when someone invokes cekit build [builder]. Especially since those images cannot be trivially built (#57)

Perhaps we should track the latest/supported/preferred image with image.yaml instead (UBI8/JDK11).

We could do it in phases, phase one might be to rename image.yaml but not put a new image.yaml in place (and fix any problems in CI/CD etc)

A later phase might be to add a symlink from image.yaml to the preferred image.

[jmtd]

Done!