Determine chart digest by manifest (#8249)

Currently, whenever the chart is printed, the digest of the .tar.gz
content layer is printed as the digest. The manifest digest is important
for OCI purposes, particularly in pushing to a registry.

Resolves #8248.

Signed-off-by: Peter Engelbert <pmengelbert@gmail.com>

internal/experimental/registry/client.go

@@ -240,7 +240,7 @@ func (c *Client) PrintChartTable() error {
 // printCacheRefSummary prints out chart ref summary
 func (c *Client) printCacheRefSummary(r *CacheRefSummary) {
 	fmt.Fprintf(c.out, "ref:     %s\n", r.Name)
-	fmt.Fprintf(c.out, "digest:  %s\n", r.Digest.Hex())
+	fmt.Fprintf(c.out, "digest:  %s\n", r.Manifest.Digest.Hex())
 	fmt.Fprintf(c.out, "size:    %s\n", byteCountBinary(r.Size))
 	fmt.Fprintf(c.out, "name:    %s\n", r.Chart.Metadata.Name)
 	fmt.Fprintf(c.out, "version: %s\n", r.Chart.Metadata.Version)
@@ -257,7 +257,7 @@ func (c *Client) getChartTableRows() ([][]interface{}, error) {
 		refsMap[r.Name] = map[string]string{
 			"name":    r.Chart.Metadata.Name,
 			"version": r.Chart.Metadata.Version,
-			"digest":  shortDigest(r.Digest.Hex()),
+			"digest":  shortDigest(r.Manifest.Digest.Hex()),
 			"size":    byteCountBinary(r.Size),
 			"created": timeAgo(r.CreatedAt),
 		}