[gnome-calculator] Use another mirror for mpc as the multiprecision.org one doesn't work

[Robert Roth <robertroth src gnome org>]

commit f97537cbfc8305ae798956960af69f1e139d664f
Author: Robert Roth <robert roth off gmail com>
Date:   Mon Jan 29 13:53:20 2018 +0200

    Use another mirror for mpc as the multiprecision.org one doesn't work

 org.gnome.Calculator.json |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/org.gnome.Calculator.json b/org.gnome.Calculator.json
index 6802ddd..f5e9e8a 100644
--- a/org.gnome.Calculator.json
+++ b/org.gnome.Calculator.json
@@ -45,7 +45,7 @@
             "sources": [
                 {
                     "type": "archive",
-                    "url": "http://www.multiprecision.org/mpc/download/mpc-1.0.2.tar.gz";,
+                    "url": "https://ftp.gnu.org/gnu/mpc/mpc-1.0.2.tar.gz";,
                     "sha256": "b561f54d8a479cee3bc891ee52735f18ff86712ba30f036f8b8537bae380c488"
                 }
             ]