SA-CONTRIB-2026-239: Critical severity drupal/simple_user_management vulnerability

This module lets non-administrators approve, deactivate and delete users, limited by the roles they can delegate through Role Delegation. The module doesn't sufficiently check role delegation when approving users, and offers an Activate link for blocked administrators. It also doesn't protect user 1 from being deactivated or deleted. This vulnerability is mitigated by the fact that an attacker must have a role with one of the module's additional action permissions.