deps: update undici to 7.21.0

[nodejs-github-bot]

This is an automated update of undici to 7.21.0.

Closes #61679

[nodejs-github-bot]

Review requested:

• @nodejs/security-wg

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.76%. Comparing base (ae2ffce) to head (e7bce4b).
⚠️ Report is 7 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #61683      +/-   ##
==========================================
+ Coverage   89.75%   89.76%   +0.01%     
==========================================
  Files         674      674              
  Lines      204416   204416              
  Branches    39285    39282       -3     
==========================================
+ Hits       183472   183493      +21     
+ Misses      13227    13221       -6     
+ Partials     7717     7702      -15     

see 30 files with indirect coverage changes

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[mcollina]

The CI failures are caused by a bug in undici 7.20.0 where __filename is not defined when undici is bundled inside Node.js as an internal module.

When fetch() fails, the code in index-fetch.js tries to access __filename to augment the stack trace, but this throws a ReferenceError that swallows the original error, making err.cause undefined.

Fix PR: nodejs/undici#4812

[mcollina]

This is fixed in undici v7.21.0

[mcollina]

lgtm

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/71217/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/71218/

[nodejs-github-bot]

Landed in 9afa802