lib: fix sequence argument handling in Blob constructor

[Ms2ger]

This uses the existing WebIDL infrastructure to handle the iteration over the argument correctly according to the specification.

Note that we can't avoid looping over the input twice: we only know the value of the 'endings' option after converting the blob parts into an array.

[nodejs-github-bot]

Review requested:

• @nodejs/web-standards

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.65%. Comparing base (f82525e) to head (d4ac3a5).
⚠️ Report is 12 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #62179   +/-   ##
=======================================
  Coverage   89.65%   89.65%           
=======================================
  Files         676      676           
  Lines      206541   206550    +9     
  Branches    39541    39552   +11     
=======================================
+ Hits       185171   185182   +11     
- Misses      13472    13484   +12     
+ Partials     7898     7884   -14     

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

... and 32 files with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/71668/