Docs: Correct @return value for _oembed_rest_pre_serve_request().

Follow-up to [35436].

Props justlevine.
See #63268.

git-svn-id: https://develop.svn.wordpress.org/trunk@60401 602fd350-edb4-49c9-b593-d223f7449a82

Author: SergeyBiryukov

src/wp-includes/embed.php

@@ -765,7 +765,7 @@ function wp_oembed_ensure_format( $format ) {
  * @param WP_HTTP_Response $result  Result to send to the client. Usually a `WP_REST_Response`.
  * @param WP_REST_Request  $request Request used to generate the response.
  * @param WP_REST_Server   $server  Server instance.
- * @return true
+ * @return bool True if the request was served, false otherwise.
  */
 function _oembed_rest_pre_serve_request( $served, $result, $request, $server ) {
 	$params = $request->get_params();