minor #22042 [Workflow] add Phpdoc for better IDE support (xabbuh)

This PR was merged into the 3.2 branch.

Discussion
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[Workflow] add Phpdoc for better IDE support

| Q             | A
| ------------- | ---
| Branch?       | 3.2
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets |
| License       | MIT
| Doc PR        |

Allow IDEs to provide more precise auto-completion support.

Commits
-------

916a97c834 [Workflow] add Phpdoc for better IDE support

src/Symfony/Component/Workflow/DefinitionBuilder.php

@@ -54,11 +54,17 @@ class DefinitionBuilder
         $this->initialPlace = null;
     }
 
+    /**
+     * @param string $place
+     */
     public function setInitialPlace($place)
     {
         $this->initialPlace = $place;
     }
 
+    /**
+     * @param string $place
+     */
     public function addPlace($place)
     {
         if (!preg_match('{^[\w\d_-]+$}', $place)) {
@@ -72,6 +78,9 @@ class DefinitionBuilder
         $this->places[$place] = $place;
     }
 
+    /**
+     * @param string[] $places
+     */
     public function addPlaces(array $places)
     {
         foreach ($places as $place) {