Fix link to archive site in TOC

Author: kgremban

articles/iot-hub-device-update/toc.yml

@@ -6,7 +6,7 @@ items:
   - name: What is Device Update for IoT Hub?
     href: understand-device-update.md
   - name: Device Update for IoT Hub (Public Preview Documentation)
-    href: https://docs.microsoft.com/en-us/previous-versions/azure/iot-hub-device-update/understand-device-update   
+    href: /previous-versions/azure/iot-hub-device-update/understand-device-update
 - name: Tutorials
   items:
   - name: Image update on Raspberry Pi