[gnome-continuous] Add libgd

[Emmanuele Bassi <ebassi src gnome org>]

commit a06ae39784075addf305cfd187b9bec9203d16e6
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Sun Jun 3 16:23:34 2018 +0100

    Add libgd
    
    Apparently, gedit is using a relative location instead of an actual URL
    for the libgd sub-module; we never caught this, because libgd was added
    once to the manifest, cloned, and then removed.

 manifest.json | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/manifest.json b/manifest.json
index 26cff3b..19ad069 100644
--- a/manifest.json
+++ b/manifest.json
@@ -1247,6 +1247,9 @@
                {"src": "gnome:gspell.git",
                  "name": "gspell"},
 
+                {"src": "gnome:libgd.git",
+                 "name": "libgd"},
+
                {"src": "gnome:gedit.git",
                  "name": "gedit"},