HostRegistry initialized in several places in the framework, this can
lead to the overlapping IP, even though the possibility is low it's not
zero. This PR makes host registry initialized once for the master
thread and pytest. To avoid communication between with workers, each
worker will get its own subnet that it can use solely for its own goals.
This simplifies the solution while providing the way to avoid overlapping IP's.
Closesscylladb/scylladb#28520
Refs #27429
re-implement the dtest with same name as a scylla pytest, using
a python level network proxy instead of tcpdump etc. Both to avoid
sudo and also to ensure we don't race.
v2:
* Included positive test (mode=all)
