As a part of the moving to bare pytest we need to extract the required test
environment preparation steps into pytest's hooks/fixtures.
Do this for S3 mock stuff (MinioServer, MockS3Server, and S3ProxyServer)
and for directories with test artifacts.
For compatibility reason add --test-py-init CLI option for bare pytest
test runner: need to add it to pytest command if you need test.py
stuff in your tests (boost, topology, etc.)
Also, postpone initialization of TestSuite.artifacts and TestSuite.hosts
from import-time to runtime.
Closesscylladb/scylladb#23087
Add the possibility to run boost test from pytest.
Boost facade based on code from https://github.com/pytest-dev/pytest-cpp, but enhanced and rewritten to suite better.
