minor symfony#10479 Add missing semicolon in doc (lracicot)

This PR was submitted for the master branch but it was merged into the 4.1 branch instead (closes symfony#10479).

Discussion
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Add missing semicolon in doc

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Commits
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5dcf007 Add missing semicolon in doc

security.rst

@@ -869,7 +869,7 @@ You can easily deny access from inside a controller::
     :ref:`base controller provided by Symfony <the-base-controller-class-services>`.
     It's equivalent to the following code::
 
-        use Symfony\Component\Security\Core\Authorization\AuthorizationCheckerInterface
+        use Symfony\Component\Security\Core\Authorization\AuthorizationCheckerInterface;
         use Symfony\Component\Security\Core\Exception\AccessDeniedException;
         // ...