minor #6836 Update dashboards.rst (LaurentMarquet)

This PR was merged into the 4.x branch.

Discussion
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Update dashboards.rst

With the use of AdminDashboard we don't need this use anymore

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feefc42 Update dashboards.rst

Author: javiereguiluz

doc/dashboards.rst

@@ -86,7 +86,6 @@ Now, define the main route of your dashboard class using the following PHP attri
     use EasyCorp\Bundle\EasyAdminBundle\Config\Dashboard;
     use EasyCorp\Bundle\EasyAdminBundle\Controller\AbstractDashboardController;
     use Symfony\Component\HttpFoundation\Response;
-    use Symfony\Component\Routing\Attribute\Route;
 
     #[AdminDashboard(routePath: '/admin', routeName: 'admin')]
     class DashboardController extends AbstractDashboardController