Fix exported comments enforcer in CI

Add comments where missing and fix incorrect comments

Signed-off-by: Derek McGowan <derek@mcg.dev>

images/converter/default.go

@@ -348,6 +348,7 @@ func clearDockerV1DummyID(cfg DualConfig) (bool, error) {
 	return modified, nil
 }
 
+// ObjectWithMediaType represents an object with a MediaType field
 type ObjectWithMediaType struct {
 	// MediaType appears on Docker manifests and manifest lists.
 	// MediaType does not appear on OCI manifests and index

images/converter/uncompress/uncompress.go

@@ -91,6 +91,8 @@ func LayerConvertFunc(ctx context.Context, cs content.Store, desc ocispec.Descri
 	return &newDesc, nil
 }
 
+// IsUncompressedType returns whether the provided media type is considered
+// an uncompressed layer type
 func IsUncompressedType(mt string) bool {
 	switch mt {
 	case