[pango/matthiasc/for-master] Quiet another compiler warning

[Matthias Clasen <matthiasc src gnome org>]

commit a9a7fb1b6357e1cc278dd914f6d8513885a1eaf1
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Jul 10 10:29:10 2021 -0400

    Quiet another compiler warning

 tests/test-layout.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/tests/test-layout.c b/tests/test-layout.c
index 2a57b042..ca9e5da5 100644
--- a/tests/test-layout.c
+++ b/tests/test-layout.c
@@ -363,7 +363,7 @@ test_file (const char *filename, GString *string)
   char *p;
   LayoutParams params;
   PangoFontDescription *desc;
-  PangoFontDescription *desc2;
+  const PangoFontDescription *desc2;
   guint serial;
   PangoRectangle ink_rect, logical_rect;
   PangoRectangle ink_rect1, logical_rect1;