test_runner: create reporter destination directories

[Aston8]

This creates missing parent directories before opening file-backed --test-reporter-destination outputs, so paths like coverage/lcov.info no longer fail with ENOENT when the parent directory does not exist.

It also adds a regression test for a nested reporter destination path.

Fixes #64994

[nodejs-github-bot]

Review requested:

• @nodejs/test_runner

[atlowChemi]

@Aston8 AFAICT your commit did not follow the guidelines (and is missing the Signed-Off-By footer)

Please reword the commit to make sure it meets the required standards, and then I would be happy to run CI

[ClementValot]

Bump @Aston8 🙏

[trivikr]

@Aston8 Can you please sign the first commit and force push?

It's required as per instructions

Your commit must contain the Signed-off-by line with your name and email address as an acknowledgement that you agree to the Developer Certificate of Origin.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.28%. Comparing base (fb6693e) to head (e7c01bb).
⚠️ Report is 366 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #65008   +/-   ##
=======================================
  Coverage   90.28%   90.28%           
=======================================
  Files         762      759    -3     
  Lines      247532   247608   +76     
  Branches    46690    46674   -16     
=======================================
+ Hits       223475   223554   +79     
- Misses      15491    15518   +27     
+ Partials     8566     8536   -30     

Files with missing lines	Coverage Δ
lib/internal/test_runner/utils.js	66.48% <100.00%> (+0.13%)	⬆️

... and 54 files with indirect coverage changes

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[trivikr]

Marked as blocked as PR author @Aston8 needs to sign the first commit.