add instructions to force rotation

This API call was discovered using the browser developer tools to examine the UI for environment variables and analyze the button that initiates a rotation. We need this method documented to justify using it in our internal tooling.

Author: JonathonAnderson

articles/app-service/app-service-key-vault-references.md

@@ -95,6 +95,8 @@ If the secret version isn't specified in the reference, the app uses the latest
 
 The delay is because App Service caches the values of the Key Vault references and refetches them every 24 hours. Any configuration change to the app causes an app restart and an immediate refetch of all referenced secrets.
 
+To force rotation of the Key Vault References, make an authenticated POST request to the API endpoint ```https://management.azure.com/[Resurce ID]/config/configreferences/appsettings/refresh?api-version=2022-03-01```
+
 ## <a name = "source-app-settings-from-key-vault"></a> Understand source app settings from Key Vault
 
 To use a Key Vault reference, set the reference as the value of the setting. Your app can reference the secret through its key as normal. No code changes are required.