minor #3538 litle bug (rogergerecke)

This PR was merged into the 3.0.x-dev branch.

Discussion
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litle bug

#3537

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Commits
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baa0c1e litle bug

doc/crud.rst

@@ -488,12 +488,14 @@ associated to. If you have more than one dashboard, you must also set the Dashbo
             // if your application only contains one Dashboard, it's enough
             // to define the controller related to this URL
             $url = $this->crudUrlGenerator
+                ->build()
                 ->setController(ProductCrudController::class)
                 ->setAction(Action::INDEX);
 
             // in applications containing more than one Dashboard, you must also
             // define the Dashboard associated to the URL
             $url = $this->crudUrlGenerator
+                ->build()
                 ->setDashboard(DashboardController::class)
                 ->setController(ProductCrudController::class)
                 ->setAction(Action::INDEX);