Fixed a broken link.

Author: lvicoun

xml/slemicro_nm_configuration.xml

@@ -656,7 +656,7 @@ plugins=keyfile
    On &slema;, you can also use other sections. For details, refer to
    <link xlink:href="https://linux.die.net/man/5/networkmanager.conf">networkmanager.conf(5)</link>
    or
-   <link xlink:href="https://developer-old.gnome.org/NetworkManager/stable/NetworkManager.conf.html">Gnome's
+   <link xlink:href="https://networkmanager.pages.freedesktop.org/NetworkManager/NetworkManager/NetworkManager.conf.html">Gnome's
    developer guide</link>.
   </para>
  </section>