Validate CIDR blocks with CEL cidr function

[prometherion]

The cidr function has been introduced in the CEL library starting from Kubernetes v1.33:

Kamaji could benefit from this function to decrease load on the validation webhook: however, this requires the management cluster to be at least Kubernetes v1.33.

We can't implement that right now to avoid breaking current installations, also considering our plan to simplify the trials of Kamaji — unless @bsctl has a different opinion on this.

[bsctl]

@prometherion surely we can plan it for next releases once v1.33 comes out more widely used. And it makes sense to set some restrictions on the management cluster, currently we support kubernetes starting from v1.22+ …

[prometherion]

currently we support kubernetes starting from v1.25+

@bsctl that's incorrect, we have some CEL validations in place, that has been released ~2022: we need to reduce the support matrix to avoid staying behind and having technical debt.

surely we can plan it for next releases

Couldn't agree more, for those who need to rely on non-CEL, CLASTIX offers backwards-compatible Kamaji releases (LTS).