tox >= 3.0.15 together with virtualenv >= 20.17.1 raises
strange incompatibilities and prevents the unit test run
because tox calls virtualenv in a wrong way leading to
strange error messages like:
---
usage: virtualenv ...
virtualenv: error: argument dest: destination '{check,devel,packagedoc,doc,doc_gh_pages,doc_suse,doc_man,scripts,}: /home/runner/work/kiwi/kiwi/.tox/3\n/home/runner/work/kiwi/kiwi/.tox/3.8' must not contain the path separator (:) as this would break the activation scripts
---
All this doesn't make sense to me at all and worked
without any issues before.