Kubernetes is removing support for the v1beta1 Ingress type in 1.22: https://kubernetes.io/blog/2021/07/14/upcoming-changes-in-kubernetes-1-22/#api-changes
However, we still wish to support k8s v1.16 until mid 2022 when Openshift 3 becomes out of support.
cert-manager will now use v1 Ingress if available by using the discovery API.
Signed-off-by: Jake Sanders <i@am.so-aweso.me>