ARM managementGroup scope function validate

[drewkg]

I am note sure if this is a tooling issue or schema validation issue, but when I use the managementGroup() function in a ARM template I get the following message in VS Code

Template validation failed: The template resource XXXX. The template function 'managementGroup' is not valid. Please see https://aka.ms/arm-template-expressions for usage details.. Please see https://aka.ms/arm-template-expressions for usage details.

I am specifically using managementGroup().name. The template does deploy correctly.

Resource snippet -
{
"name": "[substring(replace(guid(format('Security Center (MG {0})', managementGroup().name)), '-', ''), 0, 24)]",
"type": "Microsoft.Authorization/policyAssignments",
"apiVersion": "2021-06-01",
"location": "[parameters('location')]",
"scope": "[tenantResourceId('Microsoft.Management/managementGroups', managementGroup().name)]",
"identity": {
"type": "SystemAssigned"
},
"properties": {
"displayName": "[format('Security Center (MG {0})', managementGroup().name)]",
"description": "Applies Security Center Settings to an Azure Subscription.",
"policyDefinitionId": "[extensionResourceId(tenantResourceId('Microsoft.Management/managementGroups', managementGroup().name), 'Microsoft.Authorization/policySetDefinitions', 'securitycenter-deploy-initiative')]",
"parameters": {
"autoProvisioningSetting": {
"value": "[parameters('autoProvisioningSetting')]"
},
"logAnalytics": {
"value": "[concat('/subscriptions/', parameters('logAnalyticsSubscription'), '/resourceGroups/', parameters('logAnalyticsResourceGroup'), '/providers/Microsoft.OperationalInsights/workspaces/', parameters('logAnalyticsWorkspace'))]"
}
}
}

[StephenWeatherford]

Blocked by #1458