[Backport 2.x] Switch OSD Optimizer to rely on file hashes instead of mtimes

[opensearch-trigger-bot]

Backport 0609ecf from #8472.

[github-actions]

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[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 9 lines in your changes missing coverage. Please review.

Project coverage is 61.02%. Comparing base (effd6d5) to head (25ecf65).
Report is 59 commits behind head on 2.x.

Files with missing lines	Patch %	Lines
packages/osd-optimizer/src/optimizer/cache_keys.ts	20.00%	4 Missing ⚠️
packages/osd-optimizer/src/optimizer/get_hashes.ts	50.00%	2 Missing ⚠️
packages/osd-optimizer/src/common/bundle.ts	0.00%	1 Missing ⚠️
packages/osd-optimizer/src/node/cache.ts	66.66%	1 Missing ⚠️
...ckages/osd-optimizer/src/optimizer/bundle_cache.ts	66.66%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##              2.x    #8532   +/-   ##
=======================================
  Coverage   61.02%   61.02%           
=======================================
  Files        3768     3768           
  Lines       89520    89521    +1     
  Branches    14006    14006           
=======================================
+ Hits        54629    54630    +1     
  Misses      31487    31487           
  Partials     3404     3404           

Flag	Coverage Δ
Linux_1	29.01% <44.44%> (+<0.01%)	⬆️
Linux_2	56.39% <22.22%> (+<0.01%)	⬆️
Linux_3	37.78% <ø> (ø)
Linux_4	30.03% <22.22%> (+<0.01%)	⬆️
Windows_1	29.02% <44.44%> (+<0.01%)	⬆️
Windows_2	56.35% <22.22%> (+<0.01%)	⬆️
Windows_3	37.78% <ø> (ø)
Windows_4	30.03% <22.22%> (+<0.01%)	⬆️

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