minor #19932 [Routing] Fix broken link for UriSigner::sign method (JeanDavidDaviet)

This PR was merged into the 7.1 branch.

Discussion
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[Routing] Fix broken link for UriSigner::sign method

Minor change from  :phpmethod: into :method: causing a 404 link on the documentation page.

Commits
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69c39f5 Fix broken link for UriSigner::sign method

Author: javiereguiluz

routing.rst

@@ -2697,7 +2697,7 @@ service, which you can inject in your services or controllers::
 For security reasons, it's common to make signed URIs expire after some time
 (e.g. when using them to reset user credentials). By default, signed URIs don't
 expire, but you can define an expiration date/time using the ``$expiration``
-argument of :phpmethod:`Symfony\\Component\\HttpFoundation\\UriSigner::sign`::
+argument of :method:`Symfony\\Component\\HttpFoundation\\UriSigner::sign`::
 
     // src/Service/SomeService.php
     namespace App\Service;