Editor: Include Cover block in the list of block types registered using metadata files.

This ensures that block stylesheets are rendered properly when `should_load_separate_core_block_assets` filter is turned on.

Follow-up to [50824], [50836].

Props walbo.
Fixes #53440.

git-svn-id: https://develop.svn.wordpress.org/trunk@51176 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/blocks/index.php

@@ -52,6 +52,7 @@ function register_core_block_types_from_metadata() {
 		'code',
 		'column',
 		'columns',
+		'cover',
 		'embed',
 		'freeform',
 		'gallery',