Importer: Investigate Buildkit Cache Manifests with No Layer References
Context
During the course of: &5523 (closed) some imports are failing due to the following error:
1 error occurred:
* pre importing tagged manifests: pre importing manifest: pre importing manifest list: converting buildkit index to manifest: buildkit index has no layer references
This is unexpected, and we should investigate the manifests effected by this error and make a determination how to address this. It's possible these images simply contain no layer, but we should confirm that our compatibility code isn't encountering and edge case we haven't seen before.