Temporary fix for aks version for airflow-dp - 1.21.7 -> 1.21.9

All Submissions:

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• [NO] Have you added an explanation of what your changes do and why you'd like us to include them? Inferred by (docs)[https://docs.microsoft.com/en-us/azure/aks/supported-kubernetes-versions?tabs=azure-cli]
• [YES] I have updated the documentation accordingly.
• [NA] My code follows the code style of this project.

Current Behavior or Linked Issues

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When running airflow pipeline for AKS when airflow is enabled, error will show:

module.airflow[0].module.aks_deployment_resources.module.aks.azurerm_kubernetes_cluster.main: Still modifying... [id=/subscriptions/7c052588-ead2-45c9-9346-...nagedClusters/osdu-mvp-dp1dev-qs29-aks, 2m40s elapsed]
module.airflow[0].module.aks_deployment_resources.module.aks.azurerm_kubernetes_cluster.main: Still modifying... [id=/subscriptions/7c052588-ead2-45c9-9346-...nagedClusters/osdu-mvp-dp1dev-qs29-aks, 2m50s elapsed]
module.airflow[0].module.aks_deployment_resources.module.aks.azurerm_kubernetes_cluster.main: Still modifying... [id=/subscriptions/7c052588-ead2-45c9-9346-...nagedClusters/osdu-mvp-dp1dev-qs29-aks, 3m0s elapsed]

Error: 
The Kubernetes/Orchestrator Version "1.21.7" is not available for Node Pool "default".

Please confirm that this version is supported by the Kubernetes Cluster "osdu-mvp-dp1dev-qs29-aks"
(Resource Group "osdu-mvp-dp1dev-qs29-rg") - which may need to be upgraded first.

The Kubernetes Cluster is running version "1.21.7".

The supported Orchestrator Versions for this Node Pool/supported by this Kubernetes Cluster are:


Node Pools cannot use a version of Kubernetes that is not supported on the Control Plane. More
details can be found at https://aka.ms/version-skew-policy.


  on ../../../modules/providers/azure/aks/main.tf line 90, in resource "azurerm_kubernetes_cluster" "main":
  90: resource "azurerm_kubernetes_cluster" "main" {

It seems that version 1.21.7 is deprecated in some azure subscriptions, therefore upgrade it is needed.

Added dp terraform variable to handle AKS version more easily.

Does this introduce a breaking change?

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• [NO] It introduces fix to airflow dp AKS version.

Other information

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• This change will apply only to the airflowdp AKS.
• Blocking the RDMS resources.
• Not upgrading to 1.24 yet, due multiple dependencies on k8s resource version update