[testing] rewrite fuzzy test suite

[robomics]

Instead of depending on hictkpy, I think it would be better to write a thin-wrapper for cooler using pybind11 and write the test suite in C++.

The only annoyance with this approach, is that we need to resort to multi-processing to run queries in parallel...

While we are at it, it would be good to also include tests for the various transformers::*.