Add ASP.NET Core release notes for .NET 10 Preview 5 based on the content provided in the issue comments in dotnet/AspNetCore.Docs#35602. Edit the included content for clarity and simplicity.

The difference is that this token is auto generated during the Get Subscriptions function call in AppStoreController.cs file when var xeroNonTenantedToken = (XeroOAuth2Token) await ...