Handle cases where the WDL workflow output contains exprs

[kinow]

Closes #200

@admi2u, can you check if this branch's code works for you? It produced the blast.cwl file in this branch/pull request.

I am taking a look at the tests that broke after this change, and will push a new commit to fix it later.

Thanks Bruno

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 60.00000% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 94.65%. Comparing base (5fd1a32) to head (6ce5a7e).

:exclamation: Current head 6ce5a7e differs from pull request most recent head 87a3419. Consider uploading reports for the commit 87a3419 to get more accurate results

Files	Patch %	Lines
wdl2cwl/main.py	60.00%	1 Missing and 1 partial :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #201      +/-   ##
==========================================
- Coverage   94.97%   94.65%   -0.32%     
==========================================
  Files           7        3       -4     
  Lines         816      730      -86     
  Branches      223      217       -6     
==========================================
- Hits          775      691      -84     
+ Misses         16       14       -2     
  Partials       25       25              

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[admi2u]

@kinow Thank you very much. I am sorry for late reply. I have tested this branch, the results are consistent with your test results, the outputSource expression is wrapped in `= f"$({ ... })".

[mr-c]

@kinow, when you've got a working and tested manually written CWL conversion, please see (or take over) my work at https://github.com/common-workflow-lab/wdl-cwl-translator/pull/191/files for synthesizing new steps to deal with workflow output expressions