test: deflake cluster-concurrent-disconnect

[lpinca]

Occasionally the error code is 'ENOTCONN' on macOS. Add it as an
allowed/expected code.

Fixes: #38405

[lpinca]

Before:

$ ./tools/test.py -J --repeat=1000 test/parallel/test-cluster-concurrent-disconnect.js 
=== release test-cluster-concurrent-disconnect ===                   
Path: parallel/test-cluster-concurrent-disconnect
node:assert:123
  throw new AssertionError(obj);
  ^

AssertionError [ERR_ASSERTION]: Expected values to be strictly equal:
+ actual - expected

+ 'ENOTCONN'
- 'EPIPE'
    at Worker.<anonymous> (/Users/luigi/code/node/test/parallel/test-cluster-concurrent-disconnect.js:29:14)
    at Worker.emit (node:events:390:28)
    at ChildProcess.<anonymous> (node:internal/cluster/worker:30:12)
    at ChildProcess.emit (node:events:390:28)
    at node:internal/child_process:848:39
    at processTicksAndRejections (node:internal/process/task_queues:78:11) {
  generatedMessage: true,
  code: 'ERR_ASSERTION',
  actual: 'ENOTCONN',
  expected: 'EPIPE',
  operator: 'strictEqual'
}

...

[02:12|% 100|+ 992|-   8]: Done

After:

$ ./tools/test.py -J --repeat=1000 test/parallel/test-cluster-concurrent-disconnect.js 
[02:14|% 100|+ 1000|-   0]: Done

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/40991/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/40998/

[tniessen]

Should this only be lenient on mac?

[lpinca]

Should this only be lenient on mac?

I think it makes sense. Will update.

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/41024/

[tniessen]

Thanks for updating!

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/41034/

[nodejs-github-bot]

Landed in 977877b