cinder v2 api tests - part1

Change volume base class name:
BaseVolumeTest -> BaseVolumeV1Test
BaseVolumeAdminTest -> BaseVolumeV1AdminTest
for the support of cinder V2 test class

Implements: blueprint cinder-v2-api-tests

Change-Id: I712a90d39981564af09393ed1b7f4be12897c808
diff --git a/tempest/api/volume/admin/test_multi_backend.py b/tempest/api/volume/admin/test_multi_backend.py
index 03e8469..c563259 100644
--- a/tempest/api/volume/admin/test_multi_backend.py
+++ b/tempest/api/volume/admin/test_multi_backend.py
@@ -22,7 +22,7 @@
 LOG = logging.getLogger(__name__)
 
 
-class VolumeMultiBackendTest(base.BaseVolumeAdminTest):
+class VolumeMultiBackendTest(base.BaseVolumeV1AdminTest):
     _interface = "json"
 
     @classmethod