add light box with new screenshot

Author: duongau

articles/expressroute/expressroute-introduction.md

@@ -40,7 +40,7 @@ For more information, see the [ExpressRoute FAQ](expressroute-faqs.md).
 
 Quickly access the most important ExpressRoute resources and information with this [cheat sheet](https://download.microsoft.com/download/b/9/2/b92e3598-6e2e-4327-a87f-8dc210abca6c/AzureNetworking-ExRCheatSheet.pdf).
 
-:::image type="content" source="./media/expressroute-introduction/cheat-sheet.png" alt-text="Screenshot of the ExpressRoute cheat sheet for accessing information quickly." lightbox="./media/expressroute-introduction/cheat-sheet.png":::
+:::image type="content" source="./media/expressroute-introduction/cheat-sheet.png" alt-text="Screenshot of the ExpressRoute cheat sheet for accessing information quickly." lightbox="./media/expressroute-introduction/cheat-sheet-expanded.png":::
 
 ## Features