Add visibility to moved workflow_delete hook.

core/modules/content_moderation/src/Hook/ContentModerationHooks.php

@@ -372,7 +372,7 @@ public function workflowUpdate(WorkflowInterface $entity) {
    * Implements hook_ENTITY_TYPE_delete().
    */
   #[Hook('workflow_delete')]
-  function workflowDelete(WorkflowInterface $entity) {
+  public function workflowDelete(WorkflowInterface $entity) {
     // Delete actions for changing moderation state.
     $workflow_base_action_id = 'content_moderation_' . $entity->id();
     $entity_types = $entity->getTypePlugin()->getEntityTypes();