wip: use the classic subscription for the gallery

Jenkinsfile_k8s

@@ -174,6 +174,7 @@ pipeline {
           // Defines the following environment variables: AZURE_CLIENT_ID, AZURE_CLIENT_SECRET, AZURE_TENANT_ID, AZURE_SUBSCRIPTION_ID
           // Ref. https://plugins.jenkins.io/azure-credentials/#plugin-content-declarative-pipeline
           AZURE                         = credentials('packer-azure-serviceprincipal-sponsorship')
+          AZURE_GALLERY                 = credentials('packer-azure-serviceprincipal')
           // // Split packer plugins/configuration for each matrix cell - ref. https://www.packer.io/docs/configure
           // PACKER_PLUGIN_PATH            = "${env.WORKSPACE}/plugins"
           // Define Packer Input variables through environment variables prefixed with 'PKR_VAR_'
@@ -185,6 +186,7 @@ pipeline {
           PKR_VAR_agent_os_version      = "${env.agent_type.split('-')[1]}"
           PKR_VAR_architecture          = "${env.cpu_architecture}"
           PKR_VAR_image_type            = "${env.compute_type}"
+          PKR_VAR_azure_gallery_subscription_id = "${env.AZURE_GALLERY_SUBSCRIPTION_ID}"
           PATH                          = "${WORKSPACE}/.bin:${env.PATH}" // Required if packer needs to be installed
         }
         stages {

sources.pkr.hcl

@@ -14,7 +14,7 @@ source "azure-arm" "base" {
 
   # Where to export the image
   shared_image_gallery_destination {
-    subscription        = var.azure_subscription_id
+    subscription        = var.azure_gallery_subscription_id
     resource_group      = local.azure_destination_resource_group
     gallery_name        = "${var.build_type}_packer_images"
     # Not unique name defined in https://github.com/jenkins-infra/azure/blob/bfe56cb4f843b0c8029413090c383f7ac38dde2a/locals.tf#L4-L41

variables.pkr.hcl

@@ -25,6 +25,10 @@ variable "azure_subscription_id" {
   type    = string
   default = env("AZURE_SUBSCRIPTION_ID")
 }
+variable "azure_gallery_subscription_id" {
+  type    = string
+  default = env("AZURE_SUBSCRIPTION_ID") # allow to specify distinct subscription
+}
 variable "image_version" {
   type    = string
   default = "0.0.1" # Default is a valid version to not fail azure validation