Update routing.rst

Co-authored-by: Wouter de Jong <wouterj@users.noreply.github.com>

Author: Renan de Lima

routing.rst

@@ -474,7 +474,8 @@ You can also use these functions:
 
 .. versionadded:: 6.1
 
-    The ``service(string $alias)`` function was introduced in Symfony 6.1.
+    The ``service(string $alias)`` function and ``#[AsRoutingConditionService]`` attribute
+    was introduced in Symfony 6.1.
 
 Behind the scenes, expressions are compiled down to raw PHP. Because of this,
 using the ``condition`` key causes no extra overhead beyond the time it takes