[libpanel] build: bump GLib required version

[Christian Hergert <chergert src gnome org>]

commit cbb7a4ae19ee38794f9973714ad727ca0527dbf6
Author: Christian Hergert <chergert redhat com>
Date:   Wed Jul 27 11:48:08 2022 -0700

    build: bump GLib required version

 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/meson.build b/meson.build
index 378a86f..b12ec43 100644
--- a/meson.build
+++ b/meson.build
@@ -26,7 +26,7 @@ datadir = join_paths(prefix, get_option('datadir'))
 vapidir = join_paths(datadir, 'vala', 'vapi')
 
 # Check dependencies
-glib_req_version = '2.68'
+glib_req_version = '2.72'
 gtk_req_version = '4.3'
 adwaita_req_version = '1.0'