Add support for kubernetes 1.26.4

[gustavobsch]

Hi,

I'm trying to install this, getting the following errors. What version of kubernetes does it support?

$ kubectl apply -f deploy
deployment.apps/cfssl-issuer-controller-manager created
clusterrole.rbac.authorization.k8s.io/cfssl-issuer-manager-role configured
clusterrole.rbac.authorization.k8s.io/cfssl-issuer-proxy-role unchanged
clusterrolebinding.rbac.authorization.k8s.io/cfssl-issuer-manager-rolebinding unchanged
clusterrolebinding.rbac.authorization.k8s.io/cfssl-issuer-proxy-rolebinding unchanged
role.rbac.authorization.k8s.io/cfssl-issuer-leader-election-role created
rolebinding.rbac.authorization.k8s.io/cfssl-issuer-leader-election-rolebinding created
namespace/cfssl-issuer-system unchanged
service/cfssl-issuer-controller-manager-metrics-service unchanged
resource mapping not found for name: "cfsslclusterissuers.certmanager.thg.io" namespace: "" from "deploy/apiextensions.k8s.io_v1beta1_customresourcedefinition_cfsslclusterissuers.certmanager.thg.io.yaml": no matches for kind "CustomResourceDefinition" in version "apiextensions.k8s.io/v1beta1"
ensure CRDs are installed first
resource mapping not found for name: "cfsslissuers.certmanager.thg.io" namespace: "" from "deploy/apiextensions.k8s.io_v1beta1_customresourcedefinition_cfsslissuers.certmanager.thg.io.yaml": no matches for kind "CustomResourceDefinition" in version "apiextensions.k8s.io/v1beta1"
ensure CRDs are installed first