build: include v8_debug_helper sources in the tarball

[legendecas]

Allow building with configure flag --enable-v8debughelper with the release tarball.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/78411/

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.49%. Comparing base (a7a96c2) to head (0400fd7).
⚠️ Report is 52 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #66763      +/-   ##
==========================================
+ Coverage   90.47%   90.49%   +0.01%     
==========================================
  Files         791      797       +6     
  Lines      277088   277598     +510     
  Branches    53286    53336      +50     
==========================================
+ Hits       250703   251212     +509     
+ Misses      16805    16797       -8     
- Partials     9580     9589       +9     

see 63 files with indirect coverage changes

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