[vala/staging] tests: Update for girparser change

[Rico Tzschichholz <ricotz src gnome org>]

commit 9fecb1434e4d20f7d9f10e49375e7b6631ce732b
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Fri Dec 8 16:50:31 2017 +0100

    tests: Update for girparser change

 tests/gir/bug742012.test |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/tests/gir/bug742012.test b/tests/gir/bug742012.test
index 5ce77a6..531e1ff 100644
--- a/tests/gir/bug742012.test
+++ b/tests/gir/bug742012.test
@@ -91,5 +91,5 @@ public interface Renderer : GLib.Object {
        [CCode (cname = "gcr_renderer_set_attributes")]
        public void set_attributes (GLib.List? attrs);
        [NoAccessorMethod]
-       public abstract GLib.List attributes { owned get; set; }
+       public virtual GLib.List attributes { owned get; set; }
 }