It is possible to request in the definition of install-config.yaml for additional networks to be attached to the control-plane, workers, or all when instaling the cluster.

This step should do two things:
one: add a step to generate the desired number of networks (user input) and write their networkids to ${SHARED_DIR}/ADDITIONALNETWORKIDS so they can be read by other steps in the test.

two: add a step to look for the file ${SHARED_ID}/ADDITIONALNETWORKIDS file and use its content to delete any networks listed by their ides.
The equivalent of:
for id in $(cat ${CHARED_DIR}/ADDITIONALNETWORKDIS);
do
openstack network delete $id
done