minor #9539 Update controller.rst (zairigimad)

This PR was submitted for the 4.0 branch but it was merged into the 2.7 branch instead (closes #9539).

Discussion
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Update controller.rst

change the variable name to make it consistent with the example

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Commits
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6b738c9 Update controller.rst

Author: javiereguiluz

controller.rst

@@ -218,14 +218,14 @@ method renders a template **and** puts that content into a ``Response``
 object for you::
 
     // renders app/Resources/views/lucky/number.html.twig
-    return $this->render('lucky/number.html.twig', array('name' => $name));
+    return $this->render('lucky/number.html.twig', array('number' => $number));
 
 Templates can also live in deeper sub-directories. Just try to avoid
 creating unnecessarily deep structures::
 
     // renders app/Resources/views/lottery/lucky/number.html.twig
     return $this->render('lottery/lucky/number.html.twig', array(
-        'name' => $name,
+        'number' => $number,
     ));
 
 The Symfony templating system and Twig are explained more in the