Compute API version >= 2.37 requires a 'networks' value in
the server create request. The novaclient CLI defaults this
to 'auto' if not specified, but the novaclient ServerManager.create
python API binding code does not, as it wants clients to be explicit.
For the purposes of the OSC CLI, we should follow suit and if the
user is requesting OS_COMPUTE_API_VERSION>=2.37 without specific
nics, we should just default to 'auto'.
Change-Id: Ib760c55e31209223338a4086ff1f4fee88dc6959
Closes-Bug: #1750395