Update Podman documentation to use Quadlet for systemd deployment

Quadlet was integrated into Podman 4.4 and allows for a simplified systemd deployment (similar to docker-compose). I would have made this a PR instead of a discussion post, but since I haven't actually ran vaultwarden in production, I would like others to scrutinize the config and offer feedback first. I've made both containers rootless by adding the following to /etc/sysctl.conf Here are the files: ~/.config/containers/systemd/vaultwarden/vaultwarden.container ~/.config/containers/systemd/vaultwarden/vaultwarden.volume ~/.config/containers/systemd/networks/caddy-bridge.network ~/.config/containers/systemd/caddy/caddy.container ~/.config/containers/systemd/caddy/caddy-data.volume ~/.config/containers/systemd/caddy/caddy-config.volume The following is a separate idea of mine. Not applicable to the documentation update. ~~Since I don't administer any legitimate domains, I'm using Caddy to self-sign .lan hosts. The only is…