mu-plugins: Redirect placeholder page for the nonexistent WP 6.5.1 to…

… the page for WP 6.5.2

Fixes #92

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Co-authored-by: Peter Wilson <519727+peterwilsoncc@users.noreply.github.com>.

source/wp-content/mu-plugins/site-documentation.php

@@ -48,6 +48,9 @@ function redirect_old_content() {
 		'/documentation/category/customizing/' => '/documentation/customization/',
 		'/documentation/category/basic-usage/' => '/documentation/support-guides/',
 
+		// WordPress release that never was.
+		'/documentation/wordpress-version/version-6-5-1/' => '/documentation/wordpress-version/version-6-5-2/',
+
 		// Redirect articles to Advanced Administration handbook on devhub.
 		'/documentation/article/administration-over-ssl/'                           => 'https://developer.wordpress.org/advanced-administration/security/https/',
 		'/documentation/article/backing-up-your-database/'                          => 'https://developer.wordpress.org/advanced-administration/security/backup/database/',