update premium graphic

Author: vhorne

articles/firewall/media/overview/firewall-premium.png

@@ -7,7 +7,7 @@ ms.service: firewall
 services: firewall
 ms.topic: overview
 ms.custom: mvc, contperf-fy21q1
-ms.date: 03/09/2022
+ms.date: 03/17/2022
 
 # Customer intent: As an administrator, I want to evaluate Azure Firewall so I can determine if I want to use it.
 ---