Update TOC.yml

Added Ep.  20 to TOC

Author: AlizaBernstein

articles/defender-for-cloud/TOC.yml

@@ -534,7 +534,9 @@
     - name: Defender for Azure Cosmos DB
       href: episode-eighteen.md
     - name: Defender for DevOps
-      href: episode-nineteen.md   
+      href: episode-nineteen.md
+    - name: Cloud security explorer and Attack path analysis
+      href: episode-twenty.md   
   - name: Manage user data
     href: privacy.md
   - name: Microsoft Defender for IoT documentation