Support for Ubuntu Core 22.04

[Neirth]

I just noticed that Vaultwarden does not have support for Ubuntu Core 22.04, I think particularly that this service is a service that fits with the idea that Ubuntu Core conveys. Although in my professional life I usually stay away from Canonical systems (and many times in my personal life as well), to have several services deployed on a self-managed system like Ubuntu Core 22.04 can be quite interesting.