python3: Use next().
python3: Use next().

Use the next() function to be compatible with Python 3.

Signed-off-by: Russell Bryant <cd5d49e4d71817d0d870f02fc19163fd3c2f6d3a@ovn.org>

shettyg/ovn-kubernetes,shettyg/ovn-kubernetes,shettyg/ovn-kubernetes