remove use of explicit lockutils invocation in tests
remove use of explicit lockutils invocation in tests

Instead of passing lockutils loading explicitly in the test run
command line, provide the support for individual test classes to ask
that lock_path is setup with the REQUIRES_LOCKING = True class
parameter.

Augment all classes that currently fail without this with
REQUIRES_LOCKING = True. Hopefully many of those can be individually
removed in the future so we can get out of needing external locking in
any of our unit tests.

Change-Id: I56229e93ad61ac823646a4119a035d36c3400173

citrix-openstack-build/oslo.versionedobjects,openstack/oslo.versionedobjects