test: spin longer on flaky platforms for test-worker-prof

Try spinning longer to get more ticks on flaky platforms
and reduce flakiness.

PR-URL: #60492
Refs: https://github.com/nodejs/reliability/blob/main/reports/2025-10-29.md
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

Author: joyeecheung

test/sequential/test-worker-prof.js

@@ -16,10 +16,16 @@ if (process.argv[2] === 'child') {
   console.log('parent prof file:', parentProf);
 
   const { Worker } = require('worker_threads');
+  let spinTime = 1500;
+  if (common.isWindows || common.isMacOS || process.arch === 's390x') {
+    // Windows and MacOS tend to be flaky in CI, s390x as well.
+    // Give them more spins.
+    spinTime = 4500;
+  }
   const w = new Worker(`
   const { parentPort, workerData } = require('worker_threads');
 
-  const SPIN_MS = 1500;
+  const SPIN_MS = ${spinTime};
   const start = Date.now();
   parentPort.on('message', (data) => {
     if (Date.now() - start < SPIN_MS) {