Fixes 1570 portal deployment issue (#1572)

Author: arjenhuitema

docs/wiki/Whats-new.md

@@ -46,6 +46,7 @@ Here's what's changed in Enterprise Scale/Azure Landing Zones:
 - Disabled a Policy in the Microsoft Defender for SQL initiative. As it is not required at this stage. See [ALZ AMA FAQ](./ALZ-AMA-FAQ) for more details.
 - Changed enforcementMode of the assignment of Policy "Deploy-UserAssignedManagedIdentity-VMInsights" to Default. This is to ensure that a Resource Group and a User Assigned Managed Identity are created on new subscriptions (subscriptions that are added after the initial deployment).
 - Bug fix for Portal Accelerator. userAssignedIdentityResourceGroup has been added as output for the Portal UI, this fixes deploying the Resource Group with a custom name.
+- Bug fix for Portal Accelerator. `subscriptionIds` now uses lambda function to obtain the subscription IDs from `corpConnectedLzSubscriptionId`. This fixes the Invalid Template error when selecting a corp connected landing zone deployment.
 
 ### AMA Update for the Portal Accelerator
 

eslzArm/eslzArm.json

@@ -1209,7 +1209,7 @@
         },
         "privateDnsZonesMerge": "[if(and(contains(variables('azBackupGeoCodes'), parameters('connectivityLocation')), contains(variables('privateDnsZones'), 'privatelink.regionGeoShortCode.backup.windowsazure.com')), union(createArray(replace(variables('privateDnsZones')[0], '.regionGeoShortCode.', concat('.', variables('azBackupGeoCodes')[toLower(parameters('connectivityLocation'))], '.'))), variables('privateDnsZones')), variables('privateDnsZones'))]",
         "privateDnsZonesMergedWithBackupPlaceholderRemoved": "[filter(variables('privateDnsZonesMerge'), lambda('i', not(equals(lambdaVariables('i'), 'privatelink.regionGeoShortCode.backup.windowsazure.com'))))]",
-        "subscriptionIds": "[union(parameters('onlineLzSubscriptionId'), parameters('corpLzSubscriptionId'), parameters('corpConnectedLzSubscriptionId'), if(empty(parameters('singlePlatformSubscriptionId')), createArray(parameters('managementSubscriptionId'), parameters('connectivitySubscriptionId'), parameters('identitySubscriptionId')), createArray(parameters('singlePlatformSubscriptionId'))))]",
+        "subscriptionIds": "[union(parameters('onlineLzSubscriptionId'), parameters('corpLzSubscriptionId'), map(parameters('corpConnectedLzSubscriptionId'), lambda('sub', lambdaVariables('sub').subs)), if(empty(parameters('singlePlatformSubscriptionId')), createArray(parameters('managementSubscriptionId'), parameters('connectivitySubscriptionId'), parameters('identitySubscriptionId')), createArray(parameters('singlePlatformSubscriptionId'))))]",
         "roleDefinitions": {
             "networkContributor": "4d97b98b-1d4f-4787-a291-c67834d212e7"
         },