fix: remove preserveUnknownFields to avoid OutOfSync in ArgoCD

[Rems08]

fix(argo-rollouts): remove spec.preserveUnknownFields from CRDs to avoid Argo CD OutOfSync

What

Remove the spec.preserveUnknownFields: false key from all Argo Rollouts CRD templates.

Why

• In CRD apiextensions.k8s.io/v1, spec.preserveUnknownFields is deprecated/invalid and the behavior must be expressed with the OpenAPI extension x-kubernetes-preserve-unknown-fields inside the schema. Using the top-level field causes drift between desired and live objects. ([Kubernetes][1])
• Argo CD 3.0+ explicitly calls out that CRDs containing spec.preserveUnknownFields: false will show as OutOfSync and recommends removing the field. ([Argo CD][2])
• This aligns the chart with Helm/Argo CD guidance for managing CRDs (and avoids unnecessary diff noise during syncs). ([Argo Project][3])

Impact

• No functional change to the CRDs themselves—the field is ignored by modern API servers—but it eliminates false OutOfSync reports for users deploying this chart with Argo CD. ([Argo CD][2])

How I validated

• Reproduced OutOfSync on CRDs that included spec.preserveUnknownFields: false; removing the key restored a clean sync. (There’s also active community demand to drop the field.) ([GitHub][4])

Notes for Maintainers

I have not completed the checklist (version bump, docs, changelog, etc.). I’m short on time to go through the full contribution process, but this is a minimal, safe fix that prevents avoidable OutOfSync states for everyone using Argo CD. Please apply the change on your side and handle versioning/changelog as you see fit.

[yu-croco]

Hi, thank you for your PR. We will follow the upstream when upstream releases new version.

[yu-croco]

Since this PR doesn't satisfy the items in PR template, let us turn it into draft. Please handle them.