docs: add link to the method

:php:meth: should be used, but it does not work.

Author: kenjis

user_guide_src/source/helpers/cookie_helper.rst

@@ -37,7 +37,7 @@ The following functions are available:
     This helper function gives you friendlier syntax to set browser
     cookies. Refer to the :doc:`Response Library </outgoing/response>` for
     a description of its use, as this function is an alias for
-    ``Response::setCookie()``.
+    :php:func:`Response::setCookie() <setCookie>`.
 
 .. php:function:: get_cookie($index[, $xssClean = false])