Update docs

modules/lesson_embeds/src/EventSubscriber/RemoveXFrameOptionsSubscriber.php

@@ -16,6 +16,7 @@ class RemoveXFrameOptionsSubscriber implements EventSubscriberInterface {
    */
   public function RemoveXFrameOptions(FilterResponseEvent $event) {
     $response = $event->getResponse();
+    $response->headers->remove('X-Frame-Options');
     $response->headers->set('X-Frame-Options', 'ALLOW-FROM https://psu.instructure.com/');
     $response->headers->set('Content-Security-Policy', 'frame-ancestors https://psu.instructure.com/');
   }