[gtk/fix-memleaks] Plug a test memleak

[Matthias Clasen <matthiasc src gnome org>]

commit db126a19b600166caf3c268c3a0deca18a5c881e
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Mar 27 21:52:49 2021 -0400

    Plug a test memleak

 testsuite/gtk/stringlist.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/testsuite/gtk/stringlist.c b/testsuite/gtk/stringlist.c
index 63a1f6def4..93e9720d2c 100644
--- a/testsuite/gtk/stringlist.c
+++ b/testsuite/gtk/stringlist.c
@@ -167,7 +167,7 @@ test_create_builder (void)
   list = GTK_STRING_LIST (gtk_builder_get_object (builder, "list"));
   assert_model (list, "a b c");
 
-  g_object_unref (list);
+  g_object_unref (builder);
 }
 
 static void