worker: add ref/unref to web workers

[avivkeller]

Fixes #43583 (comment) by adding the non-standard ref and unref methods.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.14%. Comparing base (453f47a) to head (f5ec204).
⚠️ Report is 21 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff            @@
##             main   #65507    +/-   ##
========================================
  Coverage   90.14%   90.14%            
========================================
  Files         751      751            
  Lines      252709   253661   +952     
  Branches    47557    47773   +216     
========================================
+ Hits       227800   228674   +874     
- Misses      16206    16245    +39     
- Partials     8703     8742    +39     

Files with missing lines	Coverage Δ
lib/internal/webworker.js	92.79% <100.00%> (+0.09%)	⬆️

... and 56 files with indirect coverage changes

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[daeyeon]

Rather than the legacy per-object pattern, wouldn't process.ref()/.unref() (#53266) be a better fit here? It was designed for exactly this, avoiding non-standard method pollution on web platform APIs.

[avivkeller]

I totally forgot we had process.ref and process.unref! Fixed!