Support V4

[Hantse]

Describe the bug

I've setup a basic project with sample controller. I've just update the MQTTNet version to 4.

To Reproduce

Steps to reproduce the behavior:

1. Using this version of MQTTnet '4.1.3.436'.

Expected behavior

The controller is never trigger.

Additional context / logging

Some basics property is missing cf : Message in controller

[maikebing]

I forked this project, you can test if there is the same problem.
https://github.com/IoTSharp/MQTTnet.AspNetCore.Routing

[rafael-biz]

Any updates?