tempest: Obey identity_feature_enabled.api_v2_admin in a few tests

Skip tests when the endpoint is not available, which is the case in gate
after [1]. We'll enable them back once we adopt them to v3.

[1] Ic233f6b43dd1e3cfdadff0f18aba4ea78825a996

Related-Bug: #1687544
Change-Id: I8fffc50fd45e43f34ca591416924bcf29626b21f
2 files changed
tree: 6138dfa2802a72cf245c806d6a9b5a4f1dbe0e68
  1. neutron/