Default testing distro for epoxy cycle is ubuntu noble[1].
Also noble includes OVN latest LTS version i.e 24.03 so
removing build from source vars.
Also use crudini package instead of pip module as latest
pip don't allow modules to be install system wide.
[1] https://governance.openstack.org/tc/reference/runtimes/2025.1.html
Change-Id: I10a46b9f9aa1708b840353892e95069c0ffa5d06