update vendor

vendor/github.com/google/go-containerregistry/pkg/v1/tarball/image.go

@@ -23,13 +23,15 @@ import (
 	"io"
 	"io/ioutil"
 	"os"
+	"path"
+	"path/filepath"
 	"sync"
 
+	"github.com/google/go-containerregistry/internal/gzip"
 	"github.com/google/go-containerregistry/pkg/name"
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/partial"
 	"github.com/google/go-containerregistry/pkg/v1/types"
-	"github.com/google/go-containerregistry/pkg/v1/v1util"
 )
 
 type image struct {
@@ -68,6 +70,22 @@ func ImageFromPath(path string, tag *name.Tag) (v1.Image, error) {
 	return Image(pathOpener(path), tag)
 }
 
+// LoadManifest load manifest
+func LoadManifest(opener Opener) (Manifest, error) {
+	m, err := extractFileFromTar(opener, "manifest.json")
+	if err != nil {
+		return nil, err
+	}
+	defer m.Close()
+
+	var manifest Manifest
+
+	if err := json.NewDecoder(m).Decode(&manifest); err != nil {
+		return nil, err
+	}
+	return manifest, nil
+}
+
 // Image exposes an image from the tarball at the provided path.
 func Image(opener Opener, tag *name.Tag) (v1.Image, error) {
 	img := &image{
@@ -148,7 +166,7 @@ func (i *image) areLayersCompressed() (bool, error) {
 		return false, err
 	}
 	defer blob.Close()
-	return v1util.IsGzipped(blob)
+	return gzip.Is(blob)
 }
 
 func (i *image) loadTarDescriptorAndConfig() error {
@@ -216,6 +234,10 @@ func extractFileFromTar(opener Opener, filePath string) (io.ReadCloser, error) {
 			return nil, err
 		}
 		if hdr.Name == filePath {
+			if hdr.Typeflag == tar.TypeSymlink || hdr.Typeflag == tar.TypeLink {
+				currentDir := filepath.Dir(filePath)
+				return extractFileFromTar(opener, path.Join(currentDir, hdr.Linkname))
+			}
 			close = false
 			return tarFile{
 				Reader: tf,