public async Task DeleteCustomerTest()
        {
            var requestId = new GetCustomerRequest {
                IdFilter = 4
            };

            CustomerDto toDelete = _target.GetCustomer(requestId);
            // act
            Empty emptyDelete = _target.DeleteCustomer(toDelete);

            // assert
            Assert.Throws <RpcException>(() => _target.GetCustomer(requestId));
        }