[gnome-sdk-images] Try to fix vala-bootstrap

[Michael Catanzaro <mcatanzaro src gnome org>]

commit 03298f24b014f969c72a2fcb0fa5e14fd9f41752
Author: Michael Catanzaro <mcatanzaro igalia com>
Date:   Wed May 30 13:22:09 2018 -0500

    Try to fix vala-bootstrap
    
    It's unclear why this isn't needed by gnome-build-meta.

 org.gnome.Sdk.json.in | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/org.gnome.Sdk.json.in b/org.gnome.Sdk.json.in
index afdc481..37383bb 100644
--- a/org.gnome.Sdk.json.in
+++ b/org.gnome.Sdk.json.in
@@ -178,7 +178,7 @@
             "sources": [
                 {
                     "type": "git",
-                    "url": "https://gitlab.gnome.org/GNOME/vala-bootstrap.git";
+                    "url": "https://gitlab.gnome.org/Archive/vala-bootstrap.git";
                 }
             ]
         },