Gangams/extend arc k8s msi arm templates for ampls

[ganga1980]

This pull request includes changes to the arc-k8s-extension-msi-auth/existingClusterOnboarding.json and arc-k8s-extension-msi-auth/existingClusterParam.json scripts, primarily adding functionality for Azure Monitor Private Link Scope. The most significant changes include the addition of new parameters and variables, conditional logic for using Azure Monitor Private Link Scope, and new resources and deployments related to the Private Link Scope.

Addition of new parameters and variables:

• existingClusterOnboarding.json: Added useAzureMonitorPrivateLinkScope and azureMonitorPrivateLinkScopeResourceId parameters to indicate if Azure Monitor Private Link Scope should be used and to specify its Resource Id. Also added several variables related to the workspace and data collection endpoint.

Conditional logic for Azure Monitor Private Link Scope:

• existingClusterOnboarding.json: Added conditional logic for dataCollectionEndpointId and new resources and deployments, which are only created if useAzureMonitorPrivateLinkScope is true. [1] [2] [3]

Addition of new resources and deployments:

• existingClusterOnboarding.json: Added new resources of type Microsoft.Insights/dataCollectionEndpoints and new deployments for data collection rule endpoint association and Azure Monitor Private Link Scope scoped resources. These are only created if useAzureMonitorPrivateLinkScope is true. [1] [2]

Changes to existing resources:

• existingClusterOnboarding.json: Modified the description property in the properties of the existing resource of type Microsoft.ContainerService/managedClusters/providers/dataCollectionRuleAssociations.

Changes to parameter file:

• existingClusterParam.json: Added useAzureMonitorPrivateLinkScope and azureMonitorPrivateLinkScopeResourceId parameters.