feat: allow to redefine dnsPolicy

[pasteley]

Why is this pull request needed and what does it do?

This PR makes dnsPolicy configurable via deployment.dnsPolicy and adds support for https://kubernetes.io/docs/reference/generated/kubernetes-api/latest#poddnsconfig-v1-core, enabling advanced DNS configurations (e.g., custom nameservers, search domains, ndots tuning)

Summary of changes:

• Add deployment.dnsPolicy value (defaults to "Default" for backwards compatibility)
• Add deployment.dnsConfig value for custom DNS settings
• Add validation that fails if dnsPolicy=None without dnsConfig

Which issues (if any) are related?

None I am aware of

Checklist:

• I have bumped the chart version according to versioning.
• I have updated the chart changelog with all the changes that come with this pull request according to changelog.
• Any new values are backwards compatible and/or have sensible default.
• I have signed off all my commits as required by DCO.

Changes are automatically published when merged to main. They are not published on branches.

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[hagaibarel]

Hi @pasteley , I think this was already included in #246, can you please review the PR again and adapt if it's still needed?

[pasteley]

Rebased, this PR adds validation on top (fails if dnsPolicy: None without dnsConfig) and gives users explicit control over dnsPolicy instead of auto-setting it

[hagaibarel]

Thanks for the PR!