Even if you do not use docker directly, some compose files still use images from the docker’s registry. In case of its outage you can still use a mirror.
To configure podman to use google’s mirror of the registry, add the following lines to /etc/containers/registries.conf
[[registry]] prefix="docker.io" location="registry-1.docker.io" [[registry.mirror]] location="mirror.gcr.io"
For more information, please refer to the documentation