Remove legacy v2 unit tests[f-n]

There are two implementation code for similar API in Nova repository.
One is newer: v2.1 API, another is legacy: v2 API. v2.1 API has been
used as the default API since Liberty and legacy v2 API has been marked
as deprecated. We have used and tested v2.1 API so well and now is nice
time to remove legacy API code based on the consensus of the design
summit of Austin. This patch removes unit tests of legacy v2 API[f-n].

Partially implements blueprint remove-legacy-v2-api-code

Change-Id: I543bc2a9c068aae2c755f8159c7d2a9fff2c67ee

nova/tests/unit/api/openstack/compute/test_migrate_server.py

@@ -18,8 +18,6 @@ import six
 import webob
 
 from nova.api.openstack import api_version_request
-from nova.api.openstack.compute.legacy_v2.contrib import admin_actions as \
-    migrate_server_v2
 from nova.api.openstack.compute import migrate_server as \
     migrate_server_v21
 from nova import exception
@@ -271,13 +269,6 @@ class MigrateServerTestsV21(admin_only_action_common.CommonTests):
             check_response=False)
 
 
-class MigrateServerTestsV2(MigrateServerTestsV21):
-    migrate_server = migrate_server_v2
-    controller_name = 'AdminActionsController'
-    validation_error = webob.exc.HTTPBadRequest
-    _api_version = '2'
-
-
 class MigrateServerTestsV225(MigrateServerTestsV21):
 
     # We don't have disk_over_commit in v2.25