The volume v2 api was completely removed from cinder during Xena cycle. Unfortunately we didn't update the api_version parameter, which defines the cinder api version used, when we fixed the problem caused by removal of volume v2 api[1]. This change fixes the outdated default and ensures the current v3 api is used. [1]67acf2c5e9Change-Id: Id8940684c996e9c4bb615269976238d3f65e8140 (cherry picked from commit3ae0f65bbb)