Use the correct API version for MutatingAdmissionPolicy

[DockToFuture]

How to categorize this PR?

/area networking
/kind enhancement
/platform aws

What this PR does / why we need it:
MutatingAdmissionPolicy graduates from v1alpha1 → v1beta1 in Kubernetes 1.34 and to v1 (GA) in 1.36. This PR makes the Calico mutating admission policy chart use the correct API version based on the shoot's Kubernetes version, and aligns the enable/disable logic accordingly:

• < 1.34: v1alpha1, requires explicit feature gate + RuntimeConfig opt-in
• >= 1.34: v1beta1, enabled by default (can be opted out)
• >= 1.36: v1, always enabled (feature gate locked on)

Which issue(s) this PR fixes:
Fixes #

Special notes for your reviewer:

Release note:

Calico mutating admission policy chart uses the correct API version based on the shoot's Kubernetes version, and aligns the enable/disable logic accordingly.

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[github-actions]

This change enhances the Kubernetes MutatingAdmissionPolicy support by implementing version-aware API compatibility across different Kubernetes releases. The modification dynamically selects the appropriate API version (v1alpha1, v1beta1, or v1) based on the cluster's Kubernetes version and configuration, ensuring proper functionality as the MutatingAdmissionPolicy feature progresses from alpha to beta to GA status in different Kubernetes versions.

Walkthrough

• Refactor: Enhanced MutatingAdmissionPolicy version detection logic to automatically determine the correct API version (v1alpha1, v1beta1, or v1) based on Kubernetes cluster version and configuration
• Refactor: Modified chart templates to use configurable API version instead of hardcoded v1alpha1, improving compatibility across Kubernetes releases
• Refactor: Updated policy enablement logic to handle different maturity levels of the MutatingAdmissionPolicy feature across Kubernetes versions (alpha in <1.34, beta in 1.34-1.35, GA in ≥1.36)
• Test: Added comprehensive test coverage for version detection and API version selection logic

_{Model: claude-sonnet-4-20250514 | Prompt Tokens: 6282 | Completion Tokens: 257}