java codegen: expose the extension fields

[mr-c]

• test with cwljava @vedran-kasalica

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 83.31%. Comparing base (84139c7) to head (55e99c0).
⚠️ Report is 36 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #908   +/-   ##
=======================================
  Coverage   83.31%   83.31%           
=======================================
  Files          22       22           
  Lines        4952     4952           
  Branches     1185     1185           
=======================================
  Hits         4126     4126           
  Misses        548      548           
  Partials      278      278           

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[mr-c]

@vedran-kasalica I fixed cwljava, and you can see the result of this change at common-workflow-language/cwljava#193 ; can you test it?

[vedran-kasalica]

@mr-c thank you for the update, I will work on the project and test it next week and let you know!

[mr-c]

@vedran-kasalica how did the testing go?