Docs: Update `help` key documentation link in REST API response.

Props dd32, mukesh27, audrasjb, SergeyBiryukov.
Fixes #53162.
Built from https://develop.svn.wordpress.org/trunk@50840


git-svn-id: http://core.svn.wordpress.org/trunk@50449 1a063a9b-81f0-0310-95a4-ce76da25c4cd

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

@@ -1226,7 +1226,7 @@ class WP_REST_Server {
 		);
 
 		$response = new WP_REST_Response( $available );
-		$response->add_link( 'help', 'http://v2.wp-api.org/' );
+		$response->add_link( 'help', 'https://developer.wordpress.org/rest-api/' );
 		$this->add_active_theme_link_to_index( $response );
 
 		/**

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.8-alpha-50839';
+$wp_version = '5.8-alpha-50840';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.