Documentation: Update SELinux reference policy URL

Signed-off-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: Paul Moore <paul@paul-moore.com>

Documentation/admin-guide/LSM/SELinux.rst

@@ -6,7 +6,7 @@ If you want to use SELinux, chances are you will want
 to use the distro-provided policies, or install the
 latest reference policy release from
 
-	http://oss.tresys.com/projects/refpolicy
+	https://github.com/SELinuxProject/refpolicy
 
 However, if you want to install a dummy policy for
 testing, you can do using ``mdp`` provided under