According to changes [1,2], API tests' new home is under neutron/tests/api.
Change 92d2054f8a slipped through the cracks. It seems also that wrong
imports lead to tests silently dropped (i.e. not executed). This patch
rectifies the issue.
[1] https://review.openstack.org/#/c/169850/
[2] https://review.openstack.org/#/c/167320/
Change-Id: I64be376d7cff9512bd027720116dc039831e7955