Remove unnecessary extra arguments from openstack module

openstack/nodeimage.pkr.hcl

@@ -35,10 +35,5 @@ build {
     playbook_file = "../CRI_XCBC/ood-packer.yaml"
     roles_path = "./ansible/roles"
     inventory_file = "../CRI_XCBC/hosts"
-    extra_arguments = [
-      "--extra-vars", "root_ssh_key='${var.root_ssh_key}'",
-      "--user=centos",
-      #"-vvvv"
-    ]
   }
 }