Update I18N code style
Update I18N code style

Change: msg = _("Missing parameter: %s") % ("flavor",)
to : msg = _("Missing parameter: %s") % ("flavor")

No need to add comma for flavor.

Change-Id: I4f85954f7584aede86f7dc97fd5f97b709d4ad3d

hyakuhei/cleantox,zancas/hacking,openstack-dev/hacking,zancas/hacking,hyakuhei/cleantox,openstack-dev/hacking