[gtksourceview] completion: use PANGO_UNDERLINE_SINGLE_LINE

[Christian Hergert <chergert src gnome org>]

commit 9d3aac39bbcddce629e777aca61b928cbadf6068
Author: Christian Hergert <chergert redhat com>
Date:   Wed Sep 14 20:46:35 2022 -0700

    completion: use PANGO_UNDERLINE_SINGLE_LINE
    
    This just looks a bit better since we want to match under the whole line
    not just where underbar might be.

 gtksourceview/gtksourcecompletion.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/gtksourceview/gtksourcecompletion.c b/gtksourceview/gtksourcecompletion.c
index a699c058..978b3f2b 100644
--- a/gtksourceview/gtksourcecompletion.c
+++ b/gtksourceview/gtksourcecompletion.c
@@ -1594,7 +1594,7 @@ add_attributes (PangoAttrList **attrs,
                *attrs = pango_attr_list_new ();
        }
 
-       attr = pango_attr_underline_new (PANGO_UNDERLINE_SINGLE);
+       attr = pango_attr_underline_new (PANGO_UNDERLINE_SINGLE_LINE);
        attr->start_index = begin;
        attr->end_index = end;
        pango_attr_list_insert (*attrs, g_steal_pointer (&attr));