cli: override workflow parameters doesn't work for CWL

[diegodelemos]

$ reana-client run -f reana-cwl.yaml --parameter sleeptime=0
[INFO] Creating a workflow...
workflow.16
[INFO] Uploading files...
File code/helloworld.py was successfully uploaded.
File data/names.txt was successfully uploaded.
[INFO] Starting workflow...
Given parameter - sleeptime, is not in reana.yaml
workflow.16 has been started.

So parameter parsing fails (Given parameter - sleeptime, is not in reana.yaml) because for CWL the params are inside a file, see:

...
  parameters:
    input: workflow/cwl/helloworld-job.yml
workflow:
  type: cwl
  file: workflow/cwl/helloworld.cwl
...