Joining via hostname instead of IP

[Dzeri96]

Summary

I am trying to build a microk8s cluster on the edge, where most of my nodes won't have a static IP address.
I read through the issues and saw that this feature was never properly implemented, and in fact forbidden in #4397.

Why is this important?

I'm not a k8s expert, but since microk8s is marketed/optimized for the edge, I believe that resolving node addresses dynamically via DNS would be a common use case.
In my case, I'm using netbird and can get peer IPs via DNS manually, but there's no guarantee that these IPs won't change over time.

Are you interested in contributing to this feature?

Yes, though I wonder what the scope of this change would be.