fix: use null for unset REPORT_SAS

Author: jacdavi

m365/image/run_container.ps1

@@ -91,7 +91,7 @@ Foreach ($tenantConfig in $(Get-ChildItem 'input\')) {
 
         Write-Output "  Starting Upload"
         $OutPath = "$($Env:REPORT_OUTPUT)/$($ResultsFile.Name)"
-        if ($null -ne $Env:REPORT_SAS -and $Env:REPORT_SAS -ne "") {
+        if ($null -ne $Env:REPORT_SAS) {
             $OutPath += "?$($Env:REPORT_SAS)"
         }
         .\azcopy copy $ResultsFile.FullName $OutPath --output-level essential

m365/terraform/modules/container/main.tf

@@ -85,7 +85,7 @@ resource "azurerm_container_group" "aci" {
       "SECONDARY_APP_TLD" = var.secondary_app_info == null ? null : (var.secondary_app_info.environment_to_use == "commercial" ? "com" : "us")
     }
     secure_environment_variables = {
-      "REPORT_SAS"      = var.output_storage_container_sas != null ? var.output_storage_container_sas : ""
+      "REPORT_SAS"      = var.output_storage_container_sas
     }
     dynamic "ports" {
       for_each = var.subnet_ids == null ? [] : [1]