minor #12378 Update routing.rst (AleksejJur)

This PR was merged into the 4.3 branch.

Discussion
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Update routing.rst

Missing ';' in Routing Component documentation

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Commits
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a114125 Update routing.rst

Author: javiereguiluz

components/routing.rst

@@ -45,7 +45,7 @@ Here is a quick example::
     use Symfony\Component\Routing\Route;
     use Symfony\Component\Routing\RouteCollection;
 
-    $route = new Route('/blog/{slug}', ['_controller' => BlogController::class])
+    $route = new Route('/blog/{slug}', ['_controller' => BlogController::class]);
     $routes = new RouteCollection();
     $routes->add('blog_show', $route);