Fixed an XML attribute

Author: javiereguiluz

routing.rst

@@ -2061,7 +2061,7 @@ The solution is to configure the ``default_uri`` option to define the
                 https://symfony.com/schema/dic/symfony/symfony-1.0.xsd">
 
             <framework:config>
-                <framework:router default_uri="https://example.org/my/path/">
+                <framework:router default-uri="https://example.org/my/path/">
                     <!-- ... -->
                 </framework:router>
             </framework:config>