Cert-manager: Update CRDs to v1

[eyalzek]

Is your feature request related to a problem? Please describe.
apiextensions.k8s.io has been promoted to v1 as of 1.16 and v1beta1 support for it is planned to be dropped as of 1.19. https://github.com/kubernetes/kubernetes/pull/79604

Describe the solution you'd like
CRD manifests should use apiextensions.k8s.io/v1 and the format should be adapted to the new version. New features such as

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered. New feature such as defaulting can be considered if they're useful.

Environment details (if applicable):

• Kubernetes version (e.g. v1.10.2): 1.16.8
• Cloud-provider/provisioner (e.g. GKE, kops AWS, etc): GKE
• cert-manager version (e.g. v0.4.0): 1.14.3
• Install method (e.g. helm or static manifests): static

/kind feature

[meyskens]

/priority important-soon

[ckotzbauer]

The same applies to the admissionregistration.k8s.io/v1beta1 version which will also be dropped in 1.19 :wink:

[eyalzek]

@ckotzbauer opened another ticket for that one as well: https://github.com/jetstack/cert-manager/issues/2952

[meyskens]

We should release our normal CRD as v1 and our Legacy CRD as v1beta1

What needs to be done here:

• change the code generator to generate both versions. Unless we can make filter-crd do a conversion to the old version?