Block Editor: Preload settings and templates permissions.

This is a path for following changes in the Gutenberg plugin:
* [WordPress/gutenberg#42209 #42209: Post Editor: Preload templates post type permissions]
* [WordPress/gutenberg#42413 #42413: Post Editor: Avoid 403 errors for users with low permissions].

Follow-up to [43815], [44172], [46110], [51962], [52995].

Props Mamaduka, bernhard-reiter, TimothyBlynJacobs.
See #56467.

git-svn-id: https://develop.svn.wordpress.org/trunk@54084 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/edit-form-blocks.php

@@ -68,8 +68,10 @@ static function( $classes ) {
 	array( rest_get_route_for_post_type_items( 'attachment' ), 'OPTIONS' ),
 	array( rest_get_route_for_post_type_items( 'page' ), 'OPTIONS' ),
 	array( rest_get_route_for_post_type_items( 'wp_block' ), 'OPTIONS' ),
+	array( rest_get_route_for_post_type_items( 'wp_template' ), 'OPTIONS' ),
 	sprintf( '%s/autosaves?context=edit', $rest_path ),
 	'/wp/v2/settings',
+	array( '/wp/v2/settings', 'OPTIONS' ),
 );
 
 block_editor_rest_api_preload( $preload_paths, $block_editor_context );