Editor: Use defer loading strategy for block view scripts.

Props westonruter, joemcgill.
Fixes #59115.


git-svn-id: https://develop.svn.wordpress.org/trunk@56398 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/blocks.php

@@ -170,7 +170,8 @@ function register_block_script_handle( $metadata, $field_name, $index = 0 ) {
 		$script_handle,
 		$script_uri,
 		$script_dependencies,
-		isset( $script_asset['version'] ) ? $script_asset['version'] : false
+		isset( $script_asset['version'] ) ? $script_asset['version'] : false,
+		array( 'strategy' => 'defer' )
 	);
 	if ( ! $result ) {
 		return false;