Fix recursion in ACL model

[DarkSide666]

introduced in https://github.com/atk4/core/pull/246

BC break - Acl->getRules() now returns array of records instead of AccessRule model.

• that way we avoid recursion
• also it's much safer because we should not give access to unconditioned AccessRule model
• in future we can simply implement some optional caching mechanism if needed and simply store users rules data array somewhere