refactor!: retire legacy administration

BREAKING CHANGE: legacy management routes now fail closed and the legacy helper API is removed.

classes/event/service_deleted.php

@@ -25,7 +25,6 @@
 namespace local_webhooks\event;
 
 use core\event\base;
-use moodle_url;
 
 /**
  * Defines how to work with events.
@@ -55,10 +54,10 @@ class service_deleted extends base {
     /**
      * Get URL related to the action.
      *
-     * @throws \moodle_exception
+     * @return null
      */
     public function get_url() {
-        return new moodle_url('/local/webhooks/index.php');
+        return null;
     }
 
     /**