fix title

Author: thisisanniefang

articles/load-balancer/tutorial-gateway-cli.md

@@ -252,7 +252,7 @@ Use [az network lb frontend-ip update](/cli/azure/network/lb/frontend-ip#az_netw
 
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-## Chain VM (NIC IP configuration) to Gateway Load Balancer
+## Chain virtual machine to Gateway Load Balancer
 
 Alternatively, you can chain a VM's NIC IP configuration to the gateway load balancer.