document the requests constructor argument of the RequestStack class

Author: xabbuh

components/form.rst

@@ -123,8 +123,7 @@ The following snippet adds CSRF protection to the form factory::
     use Symfony\Component\Security\Csrf\TokenStorage\SessionTokenStorage;
 
     // creates a RequestStack object using the current request
-    $requestStack = new RequestStack();
-    $requestStack->push($request);
+    $requestStack = new RequestStack([$request]);
 
     $csrfGenerator = new UriSafeTokenGenerator();
     $csrfStorage = new SessionTokenStorage($requestStack);
@@ -135,6 +134,11 @@ The following snippet adds CSRF protection to the form factory::
         ->addExtension(new CsrfExtension($csrfManager))
         ->getFormFactory();
 
+.. versionadded:: 7.2
+
+    Support for passing requests to the constructor of the ``RequestStack``
+    class was introduced in Symfony 7.2.
+
 Internally, this extension will automatically add a hidden field to every
 form (called ``_token`` by default) whose value is automatically generated by
 the CSRF generator and validated when binding the form.