Update Windows Server SKU and enable security features

Author: tanmay-hc

builder/azure/arm/testdata/windows_sig.pkr.hcl

@@ -32,10 +32,14 @@ source "azure-arm" "windows-sig" {
   os_type         = "Windows"
   image_publisher = "MicrosoftWindowsServer"
   image_offer     = "WindowsServer"
-  image_sku       = "2025-datacenter-smalldisk-g2"
+  image_sku       = "2022-datacenter-smalldisk-g2"
 
   location = "South Central US"
   vm_size  = "Standard_D2s_v5"
+
+  secure_boot_enabled = true
+  vtpm_enabled        = true
+  security_type       = "TrustedLaunch"
 }
 
 build {