Add Ubuntu 22.04 support

[threepistons]

Pull Request (PR) description

Add support for Ubuntu 22.04 LTS.

• Add Ubuntu 22.04 to the supported OSes in metadata.json.
• Add a YAML file to recreate the nsswitch.conf found in a vanilla Ubuntu Server 22.04 LTS.

This Pull Request (PR) fixes the following issues

n/a

The nsswitch.conf file in the Beaker container

$ docker exec -it -u root beaker-ubuntu2204-64-1-5843dbdf9be3 bash
root@ubuntu2204-64-1:/# cat /etc/nsswitch.conf 
# This file is controlled by Puppet

passwd:     files systemd
shadow:     files
gshadow:    files
group:      files systemd
hosts:      files dns
ethers:     db files
networks:   files
protocols:  db files
rpc:        db files
services:   db files
netgroup:   nis
root@ubuntu2204-64-1:/# exit

The nsswitch.conf file from the freshly-built Ubuntu 22.04 VM

# /etc/nsswitch.conf
#
# Example configuration of GNU Name Service Switch functionality.
# If you have the `glibc-doc-reference' and `info' packages installed, try:
# `info libc "Name Service Switch"' for information about this file.

passwd:         files systemd
group:          files systemd
shadow:         files
gshadow:        files

hosts:          files dns
networks:       files

protocols:      db files
services:       db files
ethers:         db files
rpc:            db files

netgroup:       nis