[gnome-builder] doc: update repository URLs

[Christian Hergert <chergert src gnome org>]

commit b1b469ab20b0d291403501074b9e621b96d42d1c
Author: David Ross <davross protonmail com>
Date:   Sun Jun 17 12:24:38 2018 +0100

    doc: update repository URLs

 doc/help/contributing/code.rst | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/doc/help/contributing/code.rst b/doc/help/contributing/code.rst
index 3813b1680..850a150c0 100644
--- a/doc/help/contributing/code.rst
+++ b/doc/help/contributing/code.rst
@@ -37,7 +37,7 @@ You might find yourself running Builder from Builder.
 By default, that will activate and bring-forward your previous instance of Builder.
 If you run Builder from the command-line with ``--standalone``, it will not communicate with another 
instance of Builder.
 
-.. _libide: https://git.gnome.org//browse/gnome-builder/tree/libide/
-.. _git: https://git.gnome.org//browse/gnome-builder/tree/plugins/git/
-.. _`existing plugins`: https://git.gnome.org//browse/gnome-builder/tree/plugins/
+.. _libide: https://gitlab.gnome.org/GNOME/gnome-builder/tree/master/src/libide/
+.. _git: https://gitlab.gnome.org/GNOME/gnome-builder/tree/master/src/plugins/git
+.. _`existing plugins`: https://gitlab.gnome.org/GNOME/gnome-builder/tree/master/src/plugins