child_process: clear timeout timer on spawn error

[zeexzeex]

spawn() with a timeout hangs for the full timeout when the child fails to spawn.

const { spawn } = require('child_process');
const start = Date.now();
const child = spawn('node', ['--version'], { cwd: '/nonexistent', timeout: 5000 });
child.on('error', (e) => console.log('error', Date.now() - start, e.code));
process.on('exit', () => console.log('exiting', Date.now() - start));

error 8 ENOENT
exiting 5026

The timer is cleared on 'exit', but a spawn failure gets exitCode < 0 in onexit and emits 'error' instead, so the timer stays armed and holds the event loop open.

'close' is emitted in both cases, and exec() already clears its timer from both 'close' and 'error'. Switching the listener to 'close' covers the failure path without changing the success path.

The added test asserts on process.getActiveResourcesInfo() rather than elapsed time, so it does not depend on timing.

Fixes: #65504

[github-actions]

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[panva]

Duplicate of #65506

[zeexzeex]

Sorry for the noise, I missed #65506 when checking for existing work. Closing it.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.19%. Comparing base (7055c48) to head (1e5cc75).
⚠️ Report is 12 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #65929      +/-   ##
==========================================
+ Coverage   90.17%   90.19%   +0.02%     
==========================================
  Files         771      771              
  Lines      265407   265451      +44     
  Branches    50441    50460      +19     
==========================================
+ Hits       239322   239416      +94     
+ Misses      17029    16986      -43     
+ Partials     9056     9049       -7     

Files with missing lines	Coverage Δ
lib/child_process.js	94.11% <100.00%> (ø)

... and 29 files with indirect coverage changes

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