add: preserve unknown fields in vulnerabilityreport

[rndmh3ro]

Description

I built a custom operator (https://github.com/telekom-mms/trivy-dojo-report-operator) that uses the kopf-operator (github.com/nolar/kopf/) framework. This framework can act on kubernetes-resource creation. To detect which resources were already worked on, kopf adds a the last state of the resource as an annotation or status to the resource.I cannot use the annotation-feature, because of this issue: kubernetes-sigs/kubebuilder#2556 (annotations get too long).

So my proposal is to preserve unknown fields in the vulnerabilityreport-crd. This way I can add a status-field which kopf then can use to store the state.

Checklist

• I've read the guidelines for contributing to this repository.
• I've added tests that prove my fix is effective or that my feature works.
• I've updated the documentation with the relevant information (if needed).
• I've added usage information (if the PR introduces new options)
• I've included a "before" and "after" example to the description (if the PR is a user interface change).

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[chen-keinan]

@rndmh3ro thank you for the contribution , I'm happy to add such annotation however the kubebuilder:validation:XPreserveUnknownFields variant is deprecated in favor of the kubebuilder:pruning:PreserveUnknownFields variant. They function identically.

Adding docs ref better to use the 2nd one. wdyt?

[rndmh3ro]

Thanks @chen-keinan! I updated the code.

> make generate-all && make verify-generated ran successfully on my local machine.

[chen-keinan]

lgtm 🚀