Add link to old FAQ for SEO juice

-------
cc: @ggailey777

Author: ggailey777

articles/azure-functions/functions-consumption-costs.md

@@ -18,7 +18,7 @@ There are currently three types of hosting plans for an app that runs in Azure F
 
 You chose the plan that best supports your function performance and cost requirements. To learn more, see [Azure Functions scale and hosting](functions-scale.md).
 
-This article deals only with the Consumption plan, since this plan results in variable costs. 
+This article deals only with the Consumption plan, since this plan results in variable costs. This article supersedes the [Consumption plan cost billing FAQ](https://github.com/Azure/Azure-Functions/wiki/Consumption-Plan-Cost-Billing-FAQ) article.
 
 Durable Functions can also run in a Consumption plan. To learn more about the cost considerations when using Durable Functions, see [Durable Functions billing](./durable/durable-functions-billing.md).