The execution of the interoperability tests takes at the moment more then 5 hours. To speed that up the tests are run in parallel using the matrix strategy where each publisher is run against each subscriber. This takes roughly 50 minutes which is the slowest combination (opendds -> connext_dds). Normally the run would be finished after 20 minutes.
The run can still be issued manually only. When starting the workflow the user can deselect publishers and/or subscribers.
The matrix strategy also avoids code of cleaning up and avoids setting up a virtual Python environment all the time since every run is run an a fresh system. It also avoid code duplication since the run code needs to be written only once. Here is a run: https://github.com/s2e-systems/dds-rtps/actions/runs/19710790908