kind: ClusterIssuer

https://cert-manager.io/docs/tutorials/getting-started-aks-letsencrypt/

# clusterissuer-lets-encrypt-staging.yaml
apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
  name: letsencrypt-staging
spec:
  acme:
    server: https://acme-staging-v02.api.letsencrypt.org/directory
    email: $EMAIL_ADDRESS
    privateKeySecretRef:
      name: letsencrypt-staging
    solvers:
    - dns01:
        azureDNS:
          resourceGroupName: $AZURE_DEFAULTS_GROUP
          subscriptionID: $AZURE_SUBSCRIPTION_ID
          hostedZoneName: $DOMAIN_NAME
          environment: AzurePublicCloud
          managedIdentity:
            clientID: $USER_ASSIGNED_IDENTITY_CLIENT_ID

kind: Certificate, kind: Order, kind: Challenge