Regenerating CRDs to make them compatible with newer kubernetes types.

[paulfantom]

Description

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If it fixes a bug or resolves a feature request, be sure to link to that issue.

Some of the native kubernetes types used in prometheus-operator CRDs changed recently and have additional fields. This was not caught as we bumped neither controller-gen nor k8s.io/code-generator (both pinned in scripts/go.mod).

While fixing this I took a stab at simplifying process of generating CRDs. Instead of using our custom wrapper in form of generate-crd.go I switched to using controller-gen directly in Makefile.

Type of change

I also explicitly set preserveUnknownFields=false even though controller-gen defaults to that value when using CRD v1. This is explicitly fixing #4206

What type of changes does your code introduce to the Prometheus operator? Put an x in the box that apply.

• CHANGE (fix or feature that would cause existing functionality to not work as expected)
• FEATURE (non-breaking change which adds functionality)
• BUGFIX (non-breaking change which fixes an issue)
• ENHANCEMENT (non-breaking change which improves existing functionality)
• NONE (if none of the other choices apply. Example, tooling, build system, CI, docs, etc.)

Changelog entry

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Update native kubernetes fields used in prometheus-operator CRDs

[simonpasquier]

lgtm

[paulfantom]

Seems I forgot about this PR in the first place and some of this made way into master with #4346. I updated this PR to include changes which were not included in #4346 but are still relevant to the PR description.

I additionally passed generated CRDs through jq to have human-readable JSON files with CRDs.

cc @simonpasquier @fpetkovski