minor #33204 [Workflow] Added doc block for Registry::supports() (derrabus)

This PR was merged into the 4.3 branch.

Discussion
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[Workflow] Added doc block for Registry::supports()

| Q             | A
| ------------- | ---
| Branch?       | 4.3
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | N/A
| License       | MIT
| Doc PR        | N/A

Follows #33197, prepares #33198.

Commits
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c76fd13848 Added doc block for Registry::supports().

src/Symfony/Component/Workflow/Registry.php

@@ -82,6 +82,11 @@ class Registry
         return $matched;
     }
 
+    /**
+     * @param WorkflowSupportStrategyInterface $supportStrategy
+     * @param object                           $subject
+     * @param string|null                      $workflowName
+     */
     private function supports(WorkflowInterface $workflow, $supportStrategy, $subject, $workflowName): bool
     {
         if (null !== $workflowName && $workflowName !== $workflow->getName()) {