MDL-56417 session: Respect the return value of ignore_timeout_hook.

lib/classes/session/manager.php

@@ -770,7 +770,7 @@ class manager {
                 foreach ($authplugins as $authplugin) {
                     /** @var \auth_plugin_base $authplugin*/
                     if ($authplugin->ignore_timeout_hook($user, $user->sid, $user->s_timecreated, $user->s_timemodified)) {
-                        continue;
+                        continue 2;
                     }
                 }
                 self::kill_session($user->sid);