REST API: Remove a duplicate `require_once()`.

In `WP_REST_Attachments_Controller::create_item()`, `wp-admin/includes/image.php` was being `require_once()`-ed... twice. The superflous `require_once()` has been quietly removed.

Props david.binda.
Merges [44206] to trunk.
Fixes #45420.
Built from https://develop.svn.wordpress.org/trunk@44309


git-svn-id: http://core.svn.wordpress.org/trunk@44139 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/rest-api/endpoints/class-wp-rest-attachments-controller.php

@@ -174,7 +174,6 @@ class WP_REST_Attachments_Controller extends WP_REST_Posts_Controller {
 
 		// Include admin function to get access to wp_generate_attachment_metadata().
 		require_once ABSPATH . 'wp-admin/includes/media.php';
-		require_once ABSPATH . 'wp-admin/includes/image.php';
 
 		wp_update_attachment_metadata( $id, wp_generate_attachment_metadata( $id, $file ) );
 

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.1-alpha-44308';
+$wp_version = '5.1-alpha-44309';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.