[AAE-2261] [ADF] can't open the downloaded task audit file

[dhrn]

Please check if the PR fulfills these requirements

[x] The commit message follows our [guidelines](https://github.com/Alfresco/alfresco-js-api/wiki/Commit-format)
[ ] Tests for the changes have been added (for bug fixes / features)
[x] Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce? (check one with "x")

[x] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] Documentation
[ ] Other... Please describe:

What is the current behavior? (You can also link to an open issue here)

https://issues.alfresco.com/jira/browse/AAE-2261

What is the new behavior?

done

Does this PR introduce a breaking change? (check one with "x")

[ ] Yes
[x] No

If this PR contains a breaking change, please describe the impact and migration path for existing applications: ...

Other information:

[codecov-io]

Codecov Report

Merging #676 into development will decrease coverage by 0.03%.
The diff coverage is 0.00%.

@@               Coverage Diff               @@
##           development     #676      +/-   ##
===============================================
- Coverage        39.56%   39.53%   -0.04%     
===============================================
  Files              667      667              
  Lines            10359    10369      +10     
  Branches          1488     1488              
===============================================
  Hits              4099     4099              
- Misses            5932     5942      +10     
  Partials           328      328              

Impacted Files	Coverage Δ
...rc/api-legacy/activiti-rest-api/src/api/TaskApi.ts	50.00% <0.00%> (ø)
src/api/activiti-rest-api/api/tasks.api.ts	30.06% <0.00%> (-2.27%)	⬇️

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