OCPBUGS-57824 moved known issues to 1.16.0 section

Author: wgabor0427

security/cert_manager_operator/cert-manager-operator-release-notes.adoc

@@ -85,6 +85,11 @@ The peak memory use of the cert-manager components when they start up is optimiz
 * link:https://access.redhat.com/security/cve/CVE-2024-45338[CVE-2024-45338]
 * link:https://access.redhat.com/security/cve/CVE-2025-22866[CVE-2025-22866]
 
+[id="cert-manager-operator-1-16-0-known-issues_{context}"]
+=== Known Issues
+
+When using the Venafi issuer with username/password authentication in cert-manager version 1.16.0, the default client ID is hard-coded as `cert-manager.io` and cannot be customized. This limitation can affect users requiring a specific client ID for authentication with the Venafi platform. Support for configurable client IDs will be introduced in cert-manager version 1.17.0.
+
 [id="cert-manager-operator-release-notes-1-15-1_{context}"]
 == {cert-manager-operator} 1.15.1