gnu: Add ruby-taskjuggler.

gnu: Add ruby-taskjuggler.

[[PGP Signed Part:Good signature from D37D0EA7CECC3912 Giovanni Biscuolo (Xelera) <g@xelera.eu> (trust undefined) created at 2021-06-16T13:00:30+0200 using RSA]]
[1. text/x-diff; 0001-gnu-Add-ruby-taskjuggler.patch]
From 46aacfc1ab93166a289f8edb1fcd119e9145840c Mon Sep 17 00:00:00 2001
From: Giovanni Biscuolo <g@xelera.eu>
Date: Wed, 9 Jun 2021 11:57:12 +0200
Subject: [PATCH] gnu: Add ruby-taskjuggler.

* gnu/packages/ruby.scm (ruby-taskjuggler): New variable.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>