DevStack now uses identity v3 by default thus causing OSC to
only load openstack.identity.v3 commands. This prevents running
functional tests on openstack.identity.v2 commands. As a result,
this patch set skips all identity v2 functional tests to unblock
the gate.
Change-Id: I066187318be71792a966fa21226fab0d406c3758
Partial-Bug: #1539780