[gnome-builder] build: remove gtksourceview from bundled deps

[Christian Hergert <chergert src gnome org>]

commit ef8657d5b4c1016ddd52774ac7a02b09e11a2de5
Author: Christian Hergert <chergert redhat com>
Date:   Mon Dec 2 11:03:42 2019 -0800

    build: remove gtksourceview from bundled deps
    
    This is now part of the org.gnome.Sdk//master runtime.

 build-aux/flatpak/org.gnome.Builder.json | 10 ----------
 1 file changed, 10 deletions(-)
---
diff --git a/build-aux/flatpak/org.gnome.Builder.json b/build-aux/flatpak/org.gnome.Builder.json
index c489bae05..4c231430c 100644
--- a/build-aux/flatpak/org.gnome.Builder.json
+++ b/build-aux/flatpak/org.gnome.Builder.json
@@ -278,16 +278,6 @@
                 }
             ]
         },
-        {
-            "name" : "gtksourceview",
-            "buildsystem" : "meson",
-            "sources" : [
-                {
-                    "type" : "git",
-                    "url" : "https://gitlab.gnome.org/GNOME/gtksourceview.git";
-                }
-            ]
-        },
         {
             "name" : "amtk",
             "buildsystem" : "autotools",