This is all done as a user.
cat <<EOF> ~/.config/containers/registries.conf
unqualified-search-registries = ["registry.fedoraproject.org", "registry.access.redhat.com", "registry.centos.org", "docker.io"]
[[registry]]
location = "gitlab.example.com:8443"
insecure = true
EOF
podman system service --time 0
export DOCKER_HOST=unix:///run/user/$UID/podman/podman.sock