Update profiler-azure-functions.md

-------
cc: @hhunter-ms

Author: orspod

articles/azure-monitor/profiler/profiler-azure-functions.md

@@ -17,7 +17,7 @@ In this article, you'll use the Azure portal to:
 > [!NOTE]
 > You can enable the Application Insights Profiler for Azure Functions apps on the **App Service** plan. 
 
-## Pre-requisites
+## Prerequisites
 
 - [An Azure Functions app](../../azure-functions/functions-create-function-app-portal.md). Verify your Functions app is on the **App Service** plan.