[gtk-web/new-website] Fix navigation links

[Emmanuele Bassi <ebassi src gnome org>]

commit b432b2779a14efc52f897b8837516394eb1ab10a
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Tue Feb 18 19:11:29 2020 +0000

    Fix navigation links

 _data/navigation.yml | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)
---
diff --git a/_data/navigation.yml b/_data/navigation.yml
index 1e4690b..cbe1785 100644
--- a/_data/navigation.yml
+++ b/_data/navigation.yml
@@ -42,7 +42,7 @@ menu_links:
     footer: true
     section: Community
   - name: License
-    href: https://gitlab.gnome.org/GNOME/gtk/tree/master/COPYING/
+    href: https://gitlab.gnome.org/GNOME/gtk/tree/master/COPYING
     header: false
     footer: true
     section: Project
@@ -53,7 +53,7 @@ menu_links:
     footer: true
     section: Project
   - name: FAQs
-    href: https://developer.gnome.org/gtk3/stable/gtk-question-index.html/
+    href: https://developer.gnome.org/gtk3/stable/gtk-question-index.html
     header: false
     footer: true
     section: Support
@@ -180,6 +180,7 @@ sidebar_links:
     name: gtk4
     section: API References
     href: https://gnome.pages.gitlab.gnome.org/gtk/gtk/
+    external: true
   - title: GLib, GObject, GIO
     name: glib
     section: Architecture