Update upgrade-InternalBasic-To-PublicStandard.md

Author: irenehua

articles/load-balancer/upgrade-InternalBasic-To-PublicStandard.md

@@ -16,7 +16,7 @@ There are four stages in a upgrade:
 
 1. Migrate the configuration to Standard Public Load Balancer
 2. Add VMs to backend pools of Standard Public Load Balancer
-4. Set up NSG rules for Subnet/VMs that should be refrained from/to the Internet
+3. Set up NSG rules for Subnet/VMs that should be refrained from/to the Internet
 
 This article covers configuration migration. Adding VMs to backend pools may vary depending on your specific environment. However, some high-level, general recommendations [are provided](#add-vms-to-backend-pools-of-standard-load-balancer).