If a knowledge base has no access details specified, what users are able to read articles in that knowledge base?

`itil` users have specific roles, but default access for an unrestricted knowledge base is broader than just `itil` users.

While permalinks can link to articles, the underlying access control still applies, and without explicit restrictions, all active users can access them, not just those with a permalink.

By default, if no user criteria are specified for a knowledge base, all active users on the system can read articles within that knowledge base, providing broad access.

This is incorrect; access is not restricted to no users by default.

The `kb_user` role provides specific capabilities but isn't the sole group with access to an unrestricted knowledge base; all active users can access it.