Upstream CI: Disable execution of pytest tests.

The tests under 'tests/pytests' were a POC to bring tests that evaluate
the result of playbook execution on the IPA environment. This is
currently only implemented for dnszone tests, and similar test coverage
is obtained with other tests.

As there is an ongoing issue with Ansible's docker pluging
("the connection plugin 'docker' was not found"), which is stil under
investigation, by removing the pytest tests we'll remove the consistent
failures currently seen on upstream CI, and will not loose test
coverage, specially if we take into account downstream tests.

Also, a new version for the pytests will be available once multihost
testing is implemented for upstream.