refactor: remove unused private property

Author: kenjis

system/Router/AutoRouterImproved.php

@@ -58,13 +58,6 @@ final class AutoRouterImproved implements AutoRouterInterface
      */
     private bool $translateURIDashes;
 
-    /**
-     * HTTP verb for the request.
-     *
-     * @deprecated No longer used.
-     */
-    private string $httpVerb; // @phpstan-ignore-line
-
     /**
      * The namespace for controllers.
      */