fs: make `Dir` disposers idempotent

[Renegade334]

As per draft explicit resource management guidelines (#58526) regarding disposer behaviour.

refs: #58206

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 90.14%. Comparing base (5e1537c) to head (82fd894). Report is 38 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #58692      +/-   ##
==========================================
- Coverage   90.16%   90.14%   -0.03%     
==========================================
  Files         637      637              
  Lines      188098   188015      -83     
  Branches    36905    36891      -14     
==========================================
- Hits       169601   169478     -123     
- Misses      11231    11285      +54     
+ Partials     7266     7252      -14     

Files with missing lines	Coverage Δ
lib/internal/fs/dir.js	94.44% <100.00%> (-0.13%)	:arrow_down:

... and 37 files with indirect coverage changes

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[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/67446/

[nodejs-github-bot]

Landed in ce546e468aff70c43b5f6524d6472edff85aba28