Multiple Regions Deployment with Kolla in kolla-ansible : second region installation fails due to missing attribute 'system_scope'

[Chris]

**Bug Report**
Second region installation fails due to missing attribute 'system_scope'

We are installing multiple region cloud platform following the official documentation at : https://docs.openstack.org/kolla-ansible/latest/user/multi-regions.html

From globals.yml, the dict "openstack_auth" has no attribute "system_scope", resulting in the following error while deploying the second region :

FAILED! => {"msg": "The task includes an option with an undefined variable. The error was: 'dict object' has no attribute 'system_scope'\n\nThe error appears to be in '/usr/local/share/kolla-ansible/ansible/roles/nova-cell/tasks/wait_discover_computes.yml': line 8, column 7, but may\nbe elsewhere in the file depending on the exact syntax problem.\n\nThe offending line appears to be:\n\n- block:\n - name: Waiting for nova-compute services to register themselves\n ^ here\n"}

Adding 'system_scope: "all"' to the dict "openstack_auth" resolves the issue