fix: default value for $code in RedirectResponse::route()

For consistency. Other methods use null by default.

Author: kenjis

system/HTTP/RedirectResponse.php

@@ -50,7 +50,7 @@ public function to(string $uri, ?int $code = null, string $method = 'auto')
      *
      * @throws HTTPException
      */
-    public function route(string $route, array $params = [], int $code = 302, string $method = 'auto')
+    public function route(string $route, array $params = [], ?int $code = null, string $method = 'auto')
     {
         $namedRoute = $route;