Add 'system_scope' to context test
Add 'system_scope' to context test

ChangeID I02fdaccfdd002d60b0b51c5d3327c783009cf35e in oslo_context
added 'system_scope' to the context dictionary which we were
not expecting

Change-Id: I6bfa260100ac1a40dd9f2824375a5285a31d19b6

openstack/searchlight,openstack/searchlight,openstack/searchlight