Merge pull request #6271 from fuweid/move_stdout_to_stderr

ctr/snapshots/diff: show media-type in stderr

cmd/ctr/commands/snapshots/snapshots.go

@@ -133,8 +133,6 @@ var diffCommand = cli.Command{
 		labels := commands.LabelArgs(context.StringSlice("label"))
 		snapshotter := client.SnapshotService(context.GlobalString("snapshotter"))
 
-		fmt.Println(context.String("media-type"))
-
 		if context.Bool("keep") {
 			labels["containerd.io/gc.root"] = time.Now().UTC().Format(time.RFC3339)
 		}