Docs: Clarify Security Configuration availability

What does this MR do?

@cmutua & me found an internal ticket that might have been caused by the version number for this feature being off-by-one. Looking at #294076 (closed), it seems that some prep work was indeed completed for 13.9, but the issue itself was even past due 13.10.

Testing what the docs say on 13.9 & Starter, we found that the customer is right in that the configuration isn't available there, only the Audit events. Upgrading to Ultimate or to 13.10 resolves that issue, though.

Related issues

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