minor #27803 [Workflow] Update phpdoc to fit a used className (antograssiot)

This PR was merged into the 4.1 branch.

Discussion
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[Workflow] Update phpdoc to fit a used className

| Q             | A
| ------------- | ---
| Branch?       | 4.1
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        | none

It will just help IDE and static analysis tools to work correctly.

I could also add a `use Symfony\Component\Workflow\Workflow;` if you prefer

Commits
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89470f19cc [Workflow] Update phpdoc to fit a used className

src/Symfony/Component/Workflow/Event/Event.php

@@ -30,10 +30,10 @@ class Event extends BaseEvent
     private $workflowName;
 
     /**
-     * @param object     $subject
-     * @param Marking    $marking
-     * @param Transition $transition
-     * @param Workflow   $workflow
+     * @param object            $subject
+     * @param Marking           $marking
+     * @param Transition        $transition
+     * @param WorkflowInterface $workflow
      */
     public function __construct($subject, Marking $marking, Transition $transition, $workflow = null)
     {