Return complete response from availability_zone_client

Currently compute availability_zone_client returns Response by removing
top key from Response.
For example-
return service_client.ResponseBodyList(resp, body['availabilityZoneInfo'])

As service clients are in direction to move to Tempest-lib, all
service clients should return Response without any truncation.
One good example is Resource pagination links which are lost with current
way of return value. Resource pagination links are present in parallel
(not inside) to top key of Response.

This patch makes compute availability_zone_client to return complete
Response body.

Change-Id: I593d09fcae8b7973d5f4232408c91f046022fe99
Implements: blueprint method-return-value-and-move-service-clients-to-lib
3 files changed