test: make test-worker-prof more tolerant

It seems after the recent V8 upgrade, it's no longer safe to assume
there'll be 15 ticks per 1500ms. Lower it to 10 ticks.

PR-URL: #60272
Refs: https://github.com/nodejs/reliability/blob/main/reports/2025-10-15.md
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>

Author: joyeecheung

test/sequential/test-worker-prof.js

@@ -77,7 +77,7 @@ if (process.argv[2] === 'child') {
   // When not tracking Worker threads, only 1 or 2 ticks would
   // have been recorded.
   // prof_sampling_interval is by default 1 millisecond. A higher SPIN_MS
-  // should result in more ticks, while 15 should be safe on most machines.
-  assert(workerTicks.length > 15, `worker ticks <= 15:\n${workerTicks.join('\n')}`);
-  assert(parentTicks.length > 15, `parent ticks <= 15:\n${parentTicks.join('\n')}`);
+  // should result in more ticks, while 10 should be safe on most machines.
+  assert(workerTicks.length > 10, `worker ticks <= 10:\n${workerTicks.join('\n')}`);
+  assert(parentTicks.length > 10, `parent ticks <= 10:\n${parentTicks.join('\n')}`);
 }