V4: Mock Raise DisconnectedAsync

Hi,

I want to raise an event from Mock.
With this example I'm getting System.Reflection.TargetParameterCountException: 'Parameter count mismatch.'
What is the right way to configure Raises() for DisconnectedAsync?
```csharp
mockClient
.Setup(c => c.DisconnectAsync(
It.IsAny(),
CancellationToken.None))
.Returns(Task.FromResult(new MqttClientConnectResult()))
.Raises(x => x.DisconnectedAsync += null, new MqttClientDisconnectedEventArgs());
```

Thanks!