fix: avoid thread blocking in ParallelSink

[ndr-brt]

What this PR changes/adds

Wrap the ParallelSink logic into an async bloc.

Why it does that

avoid blocking behavior on long-running transfers

Further notes

List other areas of code that have changed but are not necessarily linked to the main feature. This could be method
signature changes, package declarations, bugs that were encountered and were fixed inline, etc.

Linked Issue(s)

Closes #4330

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Codecov Report

Attention: Patch coverage is 60.86957% with 9 lines in your changes missing coverage. Please review.

Project coverage is 75.25%. Comparing base (7f20ba5) to head (d86dec0).
Report is 338 commits behind head on main.

Files	Patch %	Lines
...dc/connector/dataplane/util/sink/ParallelSink.java	72.22%	4 Missing and 1 partial ⚠️
...taplane/framework/DataPlaneFrameworkExtension.java	20.00%	4 Missing ⚠️

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Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4333      +/-   ##
==========================================
+ Coverage   71.74%   75.25%   +3.50%     
==========================================
  Files         919     1053     +134     
  Lines       18457    21136    +2679     
  Branches     1037     1183     +146     
==========================================
+ Hits        13242    15905    +2663     
+ Misses       4756     4714      -42     
- Partials      459      517      +58     

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