[glibmm] glib/glibmm.h: Update the link to the gtkmm tutorial

[Kjell Ahlstedt <kjellahl src gnome org>]

commit ef81cfc0cdc7e6e56945b03bbece261e0e725b61
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Mon Sep 19 10:59:35 2022 +0200

    glib/glibmm.h: Update the link to the gtkmm tutorial

 glib/glibmm.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/glib/glibmm.h b/glib/glibmm.h
index 5e3b278d..7ea7b9fa 100644
--- a/glib/glibmm.h
+++ b/glib/glibmm.h
@@ -26,7 +26,7 @@
  * glibmm is the official C++ interface for the popular cross-platform library %Glib.
  * It provides non-UI API that is not available in standard C++ and makes it
  * possible for gtkmm to wrap GObject-based APIs.
- * See also the <a href="https://library.gnome.org/devel/gtkmm-tutorial/stable/";>
+ * See also the <a href="https://gnome.pages.gitlab.gnome.org/gtkmm-documentation/";>
  * Programming with gtkmm</a> book for a tutorial on programming with gtkmm and
  * glibmm.
  *