[gnome-klotski/arnaudb/wip/gtk4] Try to fix CI.

[Arnaud B. <arnaudb src gnome org>]

commit 5440c5153cedb898ba9d85a90bce53690c4bbdac
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Mon Jun 1 23:33:57 2020 +0200

    Try to fix CI.

 build-aux/org.gnome.Klotski.json | 1 +
 1 file changed, 1 insertion(+)
---
diff --git a/build-aux/org.gnome.Klotski.json b/build-aux/org.gnome.Klotski.json
index a0b2986..16f234e 100644
--- a/build-aux/org.gnome.Klotski.json
+++ b/build-aux/org.gnome.Klotski.json
@@ -26,6 +26,7 @@
         {
             "name": "libgnome-games-support",
             "buildsystem": "meson",
+            "branch": "arnaudb/wip/gtk4",
             "sources": [{
                 "type": "git",
                 "url": "https://gitlab.gnome.org/GNOME/libgnome-games-support.git";