Comment 11 for bug 1543841

This was triggered by cliff review https://review.openstack.org/#/c/262753/ that changed an argparse default allow_abbrev=False. This is a breaking API change, and rather than change the default, a way to set allow_abbrev should have been provided/documented. https://review.openstack.org/#/c/278781/ reverted the breaking change in cliff, and will be followed by a proper way to change the argparse behaviour and some tests.