Two recent changes in CI infra have affected
whitebox_neutron_tempest_plugin jobs:
1) After updating of pep8 jobs to ubuntu-noble/python3.12, an error is
reported and this patch fixes it.
2) Tests using advanced images had issues to boot rocky 9.3 VM instances
and due to that, this patch updates it to rocky 9.5.
As a consequence of this change, virt-customize command has been
updated to:
* install tcpdump
* enable dhcp for NetworkManager
And some tests have been adapted to rocky 9.5 characteristics.
Change-Id: I489ecaf1765570e52b1f2d2676f13a0edc5f6fc4