gnu: boost: Migrate uri from bintray.

* gnu/packages/boost.scm (boost)[source]: Download from jfrog.

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

gnu/packages/boost.scm

@@ -15,6 +15,7 @@
 ;;; Copyright © 2020 Marius Bakke <mbakke@fastmail.com>
 ;;; Copyright © 2020 Jonathan Brielmaier <jonathan.brielmaier@web.de>
 ;;; Copyright © 2021 Franck Pérignon <franck.perignon@univ-grenoble-alpes.fr>
+;;; Copyright © 2021 Greg Hogan <code@greghogan.com>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -66,7 +67,7 @@
     (version "1.72.0")
     (source (origin
               (method url-fetch)
-              (uri (string-append "https://dl.bintray.com/boostorg/release/"
+              (uri (string-append "https://boostorg.jfrog.io/artifactory/main/release/"
                                   version "/source/boost_"
                                   (version-with-underscores version) ".tar.bz2"))
               (patches