Refactored catalog_service{,_info} and auth modules

Replaced service_catalog return value in auth module with new
catalog_service_info module.

Change-Id: I1ca5082d643eb97e8cb951a4bccf92b78537d917

ci/roles/auth/defaults/main.yml

@@ -0,0 +1,2 @@
+expected_fields:
+  - auth_token

ci/roles/auth/tasks/main.yml

@@ -2,5 +2,10 @@
 - name: Authenticate to the cloud
   openstack.cloud.auth:
     cloud={{ cloud }}
+  register: auth
 
-- debug: var=service_catalog
+- name: Assert return values of auth module
+  assert:
+    that:
+      # allow new fields to be introduced but prevent fields from being removed
+      - expected_fields|difference(auth.keys())|length == 0