public void WhenHandleIsNotProvided_GeneratesHandle(string handle)
            {
                var expectedHandle = Guid.NewGuid().ToString("N");

                HandleHelper.GenerateHandle().Returns(expectedHandle);
                var spec = new ContainerSpec
                {
                    Handle = handle,
                };

                var container = Service.CreateContainer(spec);

                Assert.NotEqual(handle, container.Handle);
                Assert.Equal(expectedHandle, container.Handle);
            }