conformance tests: no such file or directory (84, 85, 87, 88, 93, 107, 136, 137)

[audrium]

2021-08-30 08:59:27,720 | cwltool | MainThread | INFO | Resolved 'workflow.json#main' to 'file:///var/reana/users/00000000-0000-0000-0000-000000000000/workflows/d819503f-b90e-489c-8b4f-24db8868c4d0/workflow.json#main'
Traceback (most recent call last):
  File "/code/reana_workflow_engine_cwl/pipeline.py", line 89, in executor
    for runnable in jobs:
  File "/usr/local/lib/python3.8/site-packages/cwltool/command_line_tool.py", line 846, in job
    builder = self._init_job(job_order, runtimeContext)
  File "/usr/local/lib/python3.8/site-packages/cwltool/process.py", line 800, in _init_job
    get_listing(fs_access, job, recursive=(load_listing == "deep_listing"))
  File "/usr/local/lib/python3.8/site-packages/cwltool/utils.py", line 311, in get_listing
    get_listing(fs_access, f, recursive=recursive)
  File "/usr/local/lib/python3.8/site-packages/cwltool/utils.py", line 317, in get_listing
    for ld in fs_access.listdir(loc):
  File "/usr/local/lib/python3.8/site-packages/cwltool/stdfsaccess.py", line 57, in listdir
    for entry in os.listdir(self._abs(fn))
FileNotFoundError: [Errno 2] No such file or directory: '/var/reana/users/00000000-0000-0000-0000-000000000000/workflows/d819503f-b90e-489c-8b4f-24db8868c4d0/testdir'
ERROR Workflow error, try again with --debug for more information:
[Errno 2] No such file or directory: '/var/reana/users/00000000-0000-0000-0000-000000000000/workflows/d819503f-b90e-489c-8b4f-24db8868c4d0/testdir'
2021-08-30 08:59:28,765 | cwltool | MainThread | ERROR | Workflow error, try again with --debug for more information:
[Errno 2] No such file or directory: '/var/reana/users/00000000-0000-0000-0000-000000000000/workflows/d819503f-b90e-489c-8b4f-24db8868c4d0/testdir'
workflow done
2021-08-30 08:59:28,766 | reana-workflow-engine-cwl | MainThread | INFO | workflow done

To reproduce:

cwltest --tool /home/amecioni/.virtualenvs/cwl/bin/reana-cwl-runner --test=conformance_test_v1.0.yaml -n84 --basedir /home/amecioni/Documents/tests/common-workflow-language/v1.0   --