Jenkins waits for jMeter tests to be done and not blocking a worker

Question

I have such a case:

1. jenkins trigger a jMeter test
2. the test is running as k8s job
3. jenkins job waits for test to be done
4. results land on external storage
5. jenkins downloads the results and presents as kind of an artifact in the job

And what I want to achieve is to get rid of point nr 3 and free the worker slot.

Now I'm waiting for those tests, but I guess the best option would be periodically checking if tests are still going. I don't want to keep worker slot busy by just waiting.

Can you help me with some useful plugin or maybe other approach?

Thanks!