Help/About: Update performance improvements string.

Updates the performance improvements string with the finalized percentage improvement in the editor and to improve styling and language consistency.

Props ryelle, annezazu, peterwilsoncc.
Fixes #61320.


git-svn-id: https://develop.svn.wordpress.org/trunk@58671 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/about.php

@@ -124,8 +124,9 @@
 				<p>
 					<?php
 					printf(
-						/* translators: %s: code-formatted "data-wp-on-async", %%: escaped percent sign, leave as %%. */
-						__( '6.6 includes important updates like removing redundant WP_Theme_JSON calls, disabling autoload for large options, eliminating unnecessary polyfill dependencies, lazy loading post embeds, introducing the %s directive, and a 40%% reduction in template loading time in the editor.' ),
+						/* translators: %1$s: code-formatted "WP_Theme_JSON", %2$s: code-formatted "data-wp-on-async", %%: escaped percent sign, leave as %%. */
+						__( 'WordPress 6.6 includes important updates like removing redundant %1$s calls, disabling autoload for large options, eliminating unnecessary polyfill dependencies, lazy loading post embeds, introducing the %2$s directive, and a 33%% reduction in template loading time in the editor.' ),
+						'<code>WP_Theme_JSON</code>',
 						'<code>data-wp-on-async</code>'
 					);
 					?>