currently this double-private method of a dependency library
is used in several places (openstack.cloud._utils._is_uuid_like)
openstacksdk deliberatly chose not to depend on oslo.utils to keep
dependenies to the minimum, so it just copied several methods from it,
including the is_uuid_like.
python-openstackclient however already depends on oslo.utils, so
using the public method from oslo.utils should be preferred
and more stable.
Change-Id: I578ffa36ffb00c9d47ee12a149313201973edd32