Cleanup does not work for images built with Buildah

[alexey-igrychev]

Before proceeding

• I didn't find a similar issue

Version

1.2.330 / 2.10.10

How to reproduce

1. Build images using Buildah backend.
2. Attempt to run the cleanup command for the built images.
3. Observe the behavior.

Result

The cleanup command keeps the images and removes stages associated with them.

Expected result

The cleanup command should successfully keep the images and stages associated with them.

Additional information

This is related to the bug Buildah #3866. During cleanup, our logic excludes the entire stage chain by using the digest obtained after the build. With Buildah, there is currently no way to retrieve the actual digest without publishing to a container registry.

We can wait for the issue to be resolved in Buildah. Still, we will take an alternative approach by decoupling the cleanup logic from the digest in favor of image tags, which, in the case of werf, already serve as a unique identifier for the image.