Since the CNI Spec bump to v1.0 the tuning plugin no longer updates the
mac address in the cni result for 0.4.0 or below configs. I don't think
this ever worked when the cni result was converted to a different version.
A test has been added to ensure it is working for all spec versions.
Signed-off-by: Paul Holzinger <paul.holzinger@web.de>