refactor(cert-manager): remove email

- Use Prometheus to monitor the certs instead of mail
- Cloudflare API token doesn't require email like API key

system/cert-manager/templates/clusterissuer.yaml

@@ -5,13 +5,11 @@ metadata:
 spec:
   acme:
     server: https://acme-v02.api.letsencrypt.org/directory
-    email: {{ .Values.issuer.email }}
     privateKeySecretRef:
       name: letsencrypt-prod
     solvers:
     - dns01:
         cloudflare:
-          email: {{ .Values.issuer.email }}
           apiTokenSecretRef:
             name: cloudflare-api-token
             key: api-token

system/cert-manager/values.yaml

@@ -4,6 +4,3 @@ cert-manager:
     enabled: true
     servicemonitor:
       enabled: true
-
-issuer:
-  email: mail@khuedoan.com