Merge pull request #264217 from duongau/patch-13

Front Door FAQ - update firstparty tag information

Author: prmerger-automator[bot]

articles/frontdoor/front-door-faq.yml

@@ -198,7 +198,7 @@ sections:
 
           - The *AzureFrontDoor.Backend* service tag contains the IP addresses that Front Door uses to access your origins. You can apply this service tag when you [configure security for your origins](origin-security.md).
           - The *AzureFrontDoor.Frontend* service tag contains the IP addresses that clients use to reach Front Door. You can apply the `AzureFrontDoor.Frontend` service tag when you want to control the outbound traffic that can connect to services behind Azure Front Door.
-          - The *AzureFrontDoor.FirstParty* service tag is for internal use within Azure.
+          - The *AzureFrontDoor.FirstParty* service tag is reserved for a select group of Microsoft services hosted on Azure Front Door. 
           
           For more information on Azure Front Door service tags scenarios, see [available service tags](../virtual-network/service-tags-overview.md#available-service-tags).