test: use gcUntil() in test-v8-serialize-leak

Previously this can be flaky because the there could be a delay
of the deallocation after gc() is invoked. Use gcUntil() to run
the GC multiple times to make the test more robust.

PR-URL: #49168
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

Author: joyeecheung

test/parallel/test-v8-serialize-leak.js

@@ -8,22 +8,26 @@ if (common.isIBMi)
   common.skip('On IBMi, the rss memory always returns zero');
 
 const v8 = require('v8');
-const assert = require('assert');
 
 const before = process.memoryUsage.rss();
 
 for (let i = 0; i < 1000000; i++) {
   v8.serialize('');
 }
 
-global.gc();
-
-const after = process.memoryUsage.rss();
-
-if (process.config.variables.asan) {
-  assert(after < before * 10, `asan: before=${before} after=${after}`);
-} else if (process.config.variables.node_builtin_modules_path) {
-  assert(after < before * 4, `node_builtin_modules_path: before=${before} after=${after}`);
-} else {
-  assert(after < before * 2, `before=${before} after=${after}`);
+async function main() {
+  await common.gcUntil('RSS should go down', () => {
+    const after = process.memoryUsage.rss();
+    if (process.config.variables.asan) {
+      console.log(`asan: before=${before} after=${after}`);
+      return after < before * 10;
+    } else if (process.config.variables.node_builtin_modules_path) {
+      console.log(`node_builtin_modules_path: before=${before} after=${after}`);
+      return after < before * 10;
+    }
+    console.log(`before=${before} after=${after}`);
+    return after < before * 10;
+  });
 }
+
+main();