If someone specifies a bad secret name, kube-cert-manager eats up all of the ratelimit

[mikebryant]

e.g.

- apiVersion: stable.k8s.psg.io/v1
  kind: Certificate
  spec:
    secretName: blah_api

kube-cert-manager can't create the Secret, so it just loops, repeatedly requesting the certificate but failing to store it anywhere, so it uses up all of the LetsEncrypt rate limit

If it's given a secret with an invalid name, it needs to either not process the object, or at least save the certificate and not request it repeatedly in a tight loop