Update exercise content for ExpressRoute Gateway

Author: staleycyn

Instructions/Exercises/M03-Unit 4 Configure an ExpressRoute Gateway.md

@@ -22,7 +22,7 @@ When you create a virtual network gateway, you need to specify several settings.
 
 Each virtual network can have only one virtual network gateway per gateway type. For example, you can have one virtual network gateway that uses -GatewayType VPN, and one that uses -GatewayType ExpressRoute.
 
-### Job skills
+## Job skills
 
 In this exercise, you will:
 
@@ -117,3 +117,4 @@ Congratulations on completing the lab. Here are the main takeaways for this lab.
 
 
 
+