Adds OMR 1.3.9 release notes

Author: Steven Smith

modules/mirror-registry-release-notes.adoc

@@ -11,6 +11,17 @@ These release notes track the development of the _mirror registry for Red Hat Op
 
 For an overview of the _mirror registry for Red Hat OpenShift_, see xref:../../installing/disconnected_install/installing-mirroring-creating-registry.adoc#mirror-registry-flags_installing-mirroring-creating-registry[Creating a mirror registry with mirror registry for Red Hat OpenShift].
 
+[id="mirror-registry-for-openshift-1-3-9"]
+== Mirror registry for Red Hat OpenShift 1.3.9
+
+Issued: 2023-09-19
+
+_Mirror registry for Red Hat OpenShift_ is now available with Red Hat Quay 3.8.12.
+
+The following advisory is available for the _mirror registry for Red Hat OpenShift_:
+
+* link:https://access.redhat.com/errata/RHBA-2023:5241[RHBA-2023:5241 - mirror registry for Red Hat OpenShift 1.3.9]
+
 [id="mirror-registry-for-openshift-1-3-8"]
 == Mirror registry for Red Hat OpenShift 1.3.8