Value that indicates that you want to disable unauthenticated unsubsciption of the subscription.
            If parameter is present in the request, the request has an AWS signature, and the value
            of this parameter is "true", only the topic owner and the subscription owner will be
            permitted to unsubscribe the endopint, and the Unsubscribe action will require AWS
            authentication.
            
 Declaration Syntax
 Declaration Syntax| C# | 
public string AuthenticateOnUnsubscribe { get; set; }