ci: hook network-io tests into the pipeline
This runs the "pip install" tests once for Python 2 and 3 each.
This instance will be upgraded to Heptapod 1.5.0rc (GitLab 16.11.1) on 2024-05-02 at 15:00 UTC+2
This runs the "pip install" tests once for Python 2 and 3 each.