Add Azure Functions MQTT Trigger Support

[pglombardo]

🚀 Feature Request

Azure Functions has trigger bindings for many protocols but not MQTT.

A recent customer pointed out that they are using this 3rd party library but it's limited to .NET 6.

In my search so far, I haven't found an alternative.

We should create and maintain an opensource MQTT binding for Azure.

🔈 Motivation

There is currently no way to trigger an Azure function from an MQTT message for .NET 7 or 8.

🛰 Alternatives

.NET 6 Only and hasn't been updated in quite some time: https://github.com/Hotzilla/CaseOnline.Azure.WebJobs.Extensions.Mqtt.net6

📎 Additional context