Add AKS Azure Policy quickstart

[Rebecca Calixte (Rebecca-Calixte)]

Summary

• Adds a Terraform quickstart for assigning the built-in Azure Policy pod security baseline initiative to an existing AKS cluster.
• Includes the Terraform configuration and a README with deployment and validation instructions.
• Requires an existing AKS cluster with the Azure Policy add-on enabled.

Related work item:
568336

[Vishwajeet Ranade (vranade-microsoft)]

Root cause & fix for the failing e2e-check job

Job: e2e-check run 32945850829, job 98106611353

Root cause:
quickstart/101-aks-use-azure-policy/main.tf declared data "azurerm_kubernetes_cluster" "aks" to look up the existing AKS cluster. In the e2e test, that cluster is provisioned by the quickstart/101-aks-automatic prerequisite, which creates a cluster with SKU Automatic. The azurerm_kubernetes_cluster data source in the AzureRM provider does not support the Automatic SKU, so the apply step failed with:

Error: retrieving : azurerm_kubernetes_cluster datasource does not support SKU `Automatic`

Fix:

• Removed the data "azurerm_kubernetes_cluster" "aks" block from main.tf — it was never actually referenced by the policy assignment resource, which is scoped to the resource group via data.azurerm_resource_group.aks.id, so it was dead code causing an avoidable failure.
• Added an aks_cluster_name output so the aks_cluster_name variable remains meaningfully used (per code review feedback).
• Updated README.md to match the simplified configuration.

Commits: f2ac39e0 (remove unsupported data source), 9f65487a (add output, doc updates).