Subscription Deactivate

To implement the Subscription deactivate API using the SDK, implement the abstract method processSubscriptionDeactivate from the PurchaseController:

         /// <summary>
         /// Processes Subscription Revoke requests.
         /// </summary>
         /// <returns>A <see cref="Task{T}"/> of <see cref="SubscriptionResponse"/> or an exception if subscriptions are not supported.</returns>
         protected override Task<SubscriptionResponse> ProcessSubscriptionRevoke(SubscriptionDeactivateRequest request);