@Override
  public Blob getBlob() throws LayerPropertyNotFoundException {
    throw new LayerPropertyNotFoundException(
        "Blob not available for reference layer without diff ID");
  }
Instantiate with a {@link BlobDescriptor} and no diff ID.

@param blobDescriptor the blob descriptor
jib-core/src/main/java/com/google/cloud/tools/jib/image/ReferenceNoDiffIdLayer.java