test: update test-eventsource.js to use new test runner

[tlhunter]

• updating a test to use the new test runner
• NodeConfEU says hi

[avivkeller]

IMHO this isn't needed because there's only a single test

[bengl]

The descriptive text adds extra context in case this test fails, so it seems useful even for single tests like this.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/63459/

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.40%. Comparing base (1aa7135) to head (63cfef7).
Report is 103 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #55747      +/-   ##
==========================================
- Coverage   88.40%   88.40%   -0.01%     
==========================================
  Files         654      654              
  Lines      187747   187747              
  Branches    36127    36126       -1     
==========================================
- Hits       165972   165970       -2     
- Misses      15009    15013       +4     
+ Partials     6766     6764       -2     

see 23 files with indirect coverage changes

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[lpinca]

IMHO this isn't needed because there's only a single test

I agree. It's totally useless, slows down test execution, etc. I'm not sure why this "refactor to use node:test" was chosen as a code and learn exercise when there is no official TSC stance against it and there are contributors (me in primis) who are against it. I don't block these PRs out of respect for the authors who probably don't know about it.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/63663/