Handle images with neither digest nor name

[pmengelbert]

Describe the solution you'd like Images for which the CRI reports only ImageID are problematic, because Containerd has no concept of ImageID. Ideally there would be some way to discover the digest using the imageID.

Currently these images will be removed or preserved depending on the --remove-failed flag of the trivy scanner.

Environment:

• Eraser version: v0.5.0