minor #8202 [Workflow] Fixed example usage of DefinitionBuilder (althaus)

This PR was merged into the 3.3 branch.

Discussion
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[Workflow] Fixed example usage of DefinitionBuilder

Hi,

the first code example uses the `DefinitionBuilder` with the fluent interface and a finale `build()` call. `$definition` still is the builder and not the built defintion.

Cheers
Matthias

Commits
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f1d6ea4 [WORKFLOW] Fixed example usage of DefinitionBuilder

Author: xabbuh

components/workflow.rst

@@ -44,8 +44,8 @@ these statuses are called **places**. You can define the workflow like this::
     use Symfony\Component\Workflow\Workflow;
     use Symfony\Component\Workflow\MarkingStore\SingleStateMarkingStore;
 
-    $definition = new DefinitionBuilder();
-    $definition->addPlaces(['draft', 'review', 'rejected', 'published'])
+    $definitionBuilder = new DefinitionBuilder();
+    $definition = $definitionBuilder->addPlaces(['draft', 'review', 'rejected', 'published'])
         // Transitions are defined with a unique name, an origin place and a destination place
         ->addTransition(new Transition('to_review', 'draft', 'review'))
         ->addTransition(new Transition('publish', 'review', 'published'))