[vte] build: Fix debug build

[Christian Persch <chpe src gnome org>]

commit 6a80bec4bf7a1e52057c03d2c73cce1bf248c6d7
Author: Christian Persch <chpe src gnome org>
Date:   Thu Mar 3 23:25:51 2022 +0100

    build: Fix debug build
    
    Add missing sources for the test.

 src/meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/meson.build b/src/meson.build
index 89f52985..e1abc4db 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -600,7 +600,7 @@ if get_option('sixel')
     install: false,
   )
 
-  test_sixel_sources = config_sources + glib_glue_sources + sixel_parser_sources + sixel_context_sources + 
files(
+  test_sixel_sources = config_sources + debug_sources + glib_glue_sources + sixel_parser_sources + 
sixel_context_sources + files(
     'cairo-glue.hh',
     'sixel-test.cc',
     'vtedefines.hh',