test: fix 2nd flaky blob test case

[pimterry]

#64106 fixed the flake for one test in this file, but it's still flaking (see nodejs/reliability#1596) due to the same issue in this very similar test below.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.24%. Comparing base (7036199) to head (5ccc830).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #64391      +/-   ##
==========================================
- Coverage   90.25%   90.24%   -0.01%     
==========================================
  Files         741      741              
  Lines      241207   241207              
  Branches    45424    45429       +5     
==========================================
- Hits       217696   217687       -9     
+ Misses      15087    15083       -4     
- Partials     8424     8437      +13     

see 27 files with indirect coverage changes

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[pimterry]

Main stress test: https://ci.nodejs.org/job/node-stress-single-test/788/ - failed.
PR stress test: https://ci.nodejs.org/job/node-stress-single-test/789/ - passed.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/74698/