[FAB-8309] Add CLI output to clarify channel update

This CR adds log output to the `peer channel update` command to
clarify that the update has been submitted for processing but has
not yet been validated/invalidated.

Change-Id: I3d5a6694621d9f542a4f68e8df3012a82c4f2ebb
Signed-off-by: Will Lahti <wtlahti@us.ibm.com>

peer/channel/update.go

@@ -86,5 +86,11 @@ func update(cmd *cobra.Command, args []string, cf *ChannelCmdFactory) error {
 	}
 
 	defer broadcastClient.Close()
-	return broadcastClient.Send(sCtxEnv)
+	err = broadcastClient.Send(sCtxEnv)
+	if err != nil {
+		return err
+	}
+
+	logger.Info("Successfully submitted channel update")
+	return nil
 }