Currently, it does not seem to be able to set a secret for the ingress, and thus cert-manager cannot be used out of the box.
layers:
network:
ingressClass: nginx
ingressAnnotations:
cert-manager.io/cluster-issuer: letsencrypt
ingressPath: /
ingressPathType: ImplementationSpecific
tls: true # ← suggested
Currently, it does not seem to be able to set a secret for the ingress, and thus cert-manager cannot be used out of the box.