Update TOC.yml

Author: cherylmc

articles/bastion/TOC.yml

@@ -77,7 +77,7 @@
       href: vm-upload-download-native.md
   - name: Work with NSGs
     href: bastion-nsg.md
-  - name: Health monitoring
+  - name: Monitoring
     items:
     - name: Monitoring Azure Bastion
       href: howto-metrics-monitor-alert.md