Make sure that we keep a record of the versions and boot source used
by all devices under test when running the full suite - in case we
ever suspect that there is a mismatch between the intended test image
and the actual one.
Since this test now needs to communicate with the devices, make sure
that we run the wait test first.
Due to the salting being applied to Python's `hash()` (see [1]), the
hash of an object is not stable across different Python processes. As
a result, neither are the topology mappings generated by networkx.
The upside of this is randomness that we get better test coverage over
time, especially on physical devices where the underlying hardware
could differ between ports, for example.
On the other hand, it can be very frustrating to track down a bug when
locial nodes are suffled around between phyical nodes on each
invocation of a test case.
Therefore, use a random seed by default, but allow the user to specify
a fixed value if they so choose. We then add a meta test that logs the
seed being used for the current suite - which means we can simply
copy&paste that value to rerun the suite (or single test) with the
same topology mappings.
[1]: https://docs.python.org/3/reference/datamodel.html#object.__hash__