Add security baseline to Communications Gateway docs

Author: rcdun

articles/communications-gateway/breadcrumb/toc.yml

@@ -0,0 +1,11 @@
+items:
+- name: Azure
+  tocHref: /azure/
+  topicHref: /azure/index
+  items:
+  - name: Communications Gateway
+    tocHref: /security/benchmark/azure/baselines/
+    topicHref: /azure/communications-gateway/
+  - name: Communications Gateway
+    tocHref: /azure/communications-gateway/
+    topicHref: /azure/communications-gateway/

articles/communications-gateway/security.md

@@ -9,7 +9,7 @@ ms.date: 02/09/2023
 ms.custom: template-concept
 ---
 
-# Security and Azure Communications Gateway
+# Overview of security for Azure Communications Gateway
 
 The customer data Azure Communications Gateway handles can be split into:
 
@@ -56,4 +56,5 @@ The following cipher suites are used for encrypting SIP and RTP.
 
 ## Next steps
 
+- Read the [security baseline for Azure Communications Gateway](/security/benchmark/azure/baselines/azure-communications-gateway-security-baseline?toc=/azure/communications-gateway/toc.json&bc=/azure/communications-gateway/breadcrumb/toc.json)
 - Learn about [how Azure Communications Gateway communicates with Microsoft Teams and your network](interoperability.md).

articles/communications-gateway/toc.yml

@@ -25,7 +25,11 @@ items:
   - name: Reliability
     href: reliability-communications-gateway.md
   - name: Security
-    href: security.md
+    items:
+    - name: Overview of security
+      href: security.md
+    - name: Security baseline
+      href: /security/benchmark/azure/baselines/azure-communications-gateway-security-baseline?toc=/azure/communications-gateway/toc.json&bc=/azure/communications-gateway/breadcrumb/toc.json
   - name: Monitoring
     href: monitor-azure-communications-gateway.md
 - name: How-to guides