Doocumentation in README.md states dnsname as requirement but netavark/aardvark-dns work as well

The projects README.md statess dnsname as a requirement to work with podman-compose. But with podman 4 and netavark/aardvark-dns as a network backend, this is not true anymore.

## Steps to reproduce the behavior
n/a

## Suggestion
- a podman network backend with dns name resolution available. This allows containers to be able to resolve each other if they are on the same network.
- either: [podman dnsname plugin](https://github.com/containers/dnsname) with cni network backend: It is usually found in the podman-plugins or podman-dnsname distro packages, those packages are not pulled by default and you need to install them.
- or: [netavark](https://github.com/containers/netavark)/[aardvark-dns](https://github.com/containers/aardvark-dns): Botth are usually installed on new installations of podman 4.