Fix subscriptionIds for no network deployment scenario

[arjenhuitema]

Overview/Summary

Fixes an issue where the deployment of the UAMI Resource Group fails with the following error:

{"code":"InvalidTemplateDeployment","message":"The template deployment failed with error: 'Authorization failed for template resource 'rg-ama-prod-001' of type 'Microsoft.Resources/resourceGroups'. The client '-----' with object id '-----' does not have permission to perform action 'Microsoft.Resources/subscriptions/rg-ama-prod-001/write' at scope '/subscriptions//resourceGroups/rg-ama-prod-001'.'."}

When networking is not deployed the connectivitySubscriptionId remains empty and it is included as empty in the subscriptionIds variable.

This PR fixes/adds/changes/removes

1. Adds an if statement checking whether the paramater connectivitySubscriptionId is empty. Based on the outcome, it now either creates an array of managementSubscriptionId and identitySubscriptionId, or the previous 2 and connectivitySubscriptionId.

Breaking Changes

None

Testing Evidence

Deployment

Deploying with no networking now skips creating RG and UAMI for the connectivity subscription.

Testing URLs

Azure Public

As part of this Pull Request I have

• Checked for duplicate Pull Requests
• Associated it with relevant issues, for tracking and closure.
• Ensured my code/branch is up-to-date with the latest changes in the main branch
• Performed testing and provided evidence.
• Ensured contribution guidance is followed.
• Updated relevant and associated documentation.
• Updated the "What's New?" wiki page (located: /docs/wiki/whats-new.md)

[jtracey93]

LGTM