You need to enclose the key with quotations and then escape the dots
helm install --values helm/jenkins.yml stable/jenkins --set Master.Ingress.Annotations."certmanager\.k8s\.io/cluster-issuer"=letsencrypt-staging
You need to enclose the key with quotations and then escape the dots
helm install --values helm/jenkins.yml stable/jenkins --set Master.Ingress.Annotations."certmanager\.k8s\.io/cluster-issuer"=letsencrypt-staging