refactor(fs): improve expandGlob() implementation and testing

[kt3k]

This PR improves the line coverage of fs/expand_glob.ts.

part of #3713

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 92.56%. Comparing base (41a2da4) to head (879f0f8).
Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5089      +/-   ##
==========================================
+ Coverage   92.44%   92.56%   +0.11%     
==========================================
  Files         481      481              
  Lines       38732    38708      -24     
  Branches     5446     5454       +8     
==========================================
+ Hits        35806    35829      +23     
+ Misses       2871     2824      -47     
  Partials       55       55              

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[iuioiua]

I think we should move advanceMatch() generator functions out of their respective expandGlob[Sync]() functions as advanceMatch() and advanceMatchSync().

[iuioiua]

Nice. Perhaps we can move advanceMatch() out of these functions in a follow-up PR.