upstream upnp work

[stormshield-frb]

Description

As discussed at the last maintainer call @jxs, I'm upstreaming our work on UPNP.

Our work began to allow us to listen on the unspecified address which was not working correctly since a single ListenerId can give multiple listen addresses and this was not correctly handled in the UPNP behaviour. However we also experienced some Pending blocking for ever but I don't remember the exact cause. That's why we ended up doing a more important change that we had expected. We also removed custom events from UPNP to replace them with the generic ExternalAddrConfirmed and ExternalAddrExpired.

This PR wants to be a starting point to integrate this work. IMHO, I don't thinks it is ready to merge as is, that's why I'm opening this so we can discuss what could/should be integrated and what should not.

As I have also mentioned during the call, there is some know issues:

• this solution does not handle multiple gateways.
• if you have multiple interfaces and some of them do not correspond to the gateway, we still ask the gateway to map it, which always results in an error.
• UPNP behaviour could be a little more smart and if a port is already mapped on the Gateway (resulting in an error then), it could be interesting to send a new request to the Gateway asking it to give us a random port.

Notes & open questions

N/A

Change checklist

• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• A changelog entry has been made in the appropriate crates

[mergify]

This pull request has merge conflicts. Could you please resolve them @stormshield-frb? 🙏