DDoS Protection: Included Cost Protection into feature table

Included Cost Protection into feature table.
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cc: @AbdullahBell

Author: AbdullahBell

articles/ddos-protection/ddos-protection-overview.md

@@ -44,6 +44,7 @@ The following table shows features and corresponding SKUs.
 | Active traffic monitoring & always on detection| Yes |  Yes|
 | Automatic attack mitigation | Yes | Yes |
 | Availability guarantee| Not available | Yes |
+| Cost protection | Not available | Yes |
 | Application based mitigation policies | Not available | Yes|
 | Metrics & alerts | Not available  | Yes |
 | Mitigation reports | Not available | Yes |