buffer: use Clamp conversion in Blob slice

[HoonDongKang]

This aligns Blob.prototype.slice() with the File API Web IDL definition:

Blob slice(optional [Clamp] long long start,
           optional [Clamp] long long end,
           optional DOMString contentType);

The start and end arguments should use Web IDL [Clamp] conversion.

This fixes the expected failures in Blob-slice.any.js for fractional start/end values.

Refs: https://www.w3.org/TR/FileAPI/#dfn-Blob

Testing

$ ./node test/wpt/test-blob.js Blob-slice.any.js

Files: 1/1 ran, 1 passed, 0 skipped, 0 expected failures, 0 unexpected failures, 0 unexpected passes
Subtests: 150 passed, 0 skipped, 0 expected failures, 0 unexpected failures, 0 unexpected passes

$ tools/test.py wpt/test-blob

[00:00|% 100|+   1|-   0]: Done

[nodejs-github-bot]

Review requested:

• @nodejs/web-standards

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.13%. Comparing base (0618e9f) to head (6c536b1).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #64739      +/-   ##
==========================================
- Coverage   90.14%   90.13%   -0.01%     
==========================================
  Files         743      743              
  Lines      242408   242407       -1     
  Branches    45656    45644      -12     
==========================================
- Hits       218520   218496      -24     
- Misses      15387    15401      +14     
- Partials     8501     8510       +9     

Files with missing lines	Coverage Δ
lib/internal/blob.js	89.86% <100.00%> (ø)

... and 30 files with indirect coverage changes

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[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/75136/