Updating az cli command

az cli command is invalid. Changed from azure to az

Author: Kenneth-Abrams

articles/virtual-network/virtual-networks-static-private-ip-arm-cli.md

@@ -247,7 +247,7 @@ To change the NIC for the VM used in the previous commands, complete the followi
 2. Run the **azure vm set** command to change the NIC used by the VM.
    
     ```azurecli
-    azure vm set -g TestRG -n DNS01 -N TestNIC2
+    az vm set -g TestRG -n DNS01 -N TestNIC2
     ```
 
     Expected output: