kube-libsonnet is using soon deprecated API versions

[megian]

Context

With Kubernetes v1.25 a lot of API get deprecated. The latest version of kube-libsonnet still using it.
policy/v1beta1: https://github.com/bitnami-labs/kube-libsonnet/blob/23fe9f1c4905c174c90ea1b6681fb790b6715a6c/kube.libsonnet#L268
batch/v1beta1: https://github.com/bitnami-labs/kube-libsonnet/blob/23fe9f1c4905c174c90ea1b6681fb790b6715a6c/kube.libsonnet#L531

Alternatives

• Drop the support of kube-libsonnet in Commodore

[megian]

See bitnami/kube-libsonnet#76.

[simu]

Possible options for making sure kube-libsonnet is compatible with K8s 1.25+ (no particular order):

• Hope that upstream accepts and merges Change CronJob API Version to batch/v1 and PodDisruptionBudget to policy/v1 bitnami/kube-libsonnet#76
• Vendor the library in Commodore (alongside commodore.libjsonnet) and take over maintenance for it
• Create a fork of https://github.com/bitnami-labs/kube-libsonnet in https://github.com/projectsyn, patch the fork and update Commodore to fetch the file from the projectsyn fork
• Check if https://github.com/jsonnet-libs/k8s-libsonnet is a suitable replacement (drop-in) for kube-libsonnet

[simu]

After a slightly closer look. https://github.com/jsonnet-libs/k8s-libsonnet is not a drop-in replacement for kube-libsonnet, but actually looks much nicer (and more complete -- not too surprising since the base implementation is generated from the K8s API spec). However, we could probably engineer a migration path by providing a vendored kube-libsonnet which emits deprecation warnings informing users that they should switch to k8s-libsonnet.

[megian]

The components projectsyn/component-kyverno and projectsyn/component-vault are affected and source of this issue.