github/workflows: remove crossbar_venv

It's no longer supported.

Signed-off-by: Rouven Czerwinski <r.czerwinski@pengutronix.de>

.github/workflows/reusable-unit-tests.yml

@@ -56,7 +56,7 @@ jobs:
         pylint labgrid
     - name: Test with pytest
       run: |
-        TERM=xterm pytest --cov-config .coveragerc --cov=labgrid --local-sshmanager --ssh-username runner --crossbar-venv crossbar-venv -k "not test_docker_with_daemon"
+        TERM=xterm pytest --cov-config .coveragerc --cov=labgrid --local-sshmanager --ssh-username runner -k "not test_docker_with_daemon"
     - name: Build documentation
       run: |
         make -C doc clean