REST API: don't load wp-admin/includes/admin.php on every request.

Props swissspidy.
Fixes #34395.


git-svn-id: https://develop.svn.wordpress.org/trunk@35353 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/rest-api/class-wp-rest-server.php

@@ -7,9 +7,6 @@
  * @since 4.4.0
  */
 
-/** Admin bootstrap */
-require_once( ABSPATH . 'wp-admin/includes/admin.php' );
-
 /**
  * Core class used to implement the WordPress REST API server.
  *