Move tests from volumes into volumes actions.

This patch moves the tests for the following policy actions:

  - volume_extension:volume_admin_actions:reset_status
  - volume_extension:volume_admin_actions:force_delete

into test_volume_actions_rbac because they do not belong
in test_volumes_rbac, as resetting a status of a volume [0]
and force-deleting a volume [1] are a part of the volume
actions API, not the volumes API.

As there are no tests left in test_volumes_rbac after relocating
these 2 tests, the file is deleted.

[0] https://developer.openstack.org/api-ref/block-storage/v3/index.html?expanded=reset-a-volume-s-statuses-detail
[1] https://github.com/openstack/tempest/blob/master/tempest/api/volume/admin/test_volumes_actions.py

Change-Id: Idc0286de76e1a58826f411de60988975694a2da3
2 files changed