05120edf92
The TC approved a cross project spec to stop putting db downgrade into project migration repos: https://github.com/openstack/openstack-specs/blob/master/specs/no-downward-sql-migration.rst This was done after quite a bit of feedback from the operator community, and everyone was good with it. This implements that spec for Nova, adjust the tests to pass accordingly, and changes the test which requires downgrade functions to one that prohibits them. Implements bp nova-no-downward-sql-migration Change-Id: I972e1d79e570d57baac613e56570b49e1b1da28d