test_pthread_nested_work_queue is flaky

[sbc100]

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ERROR: test_pthread_nested_work_queue (test_core.cores)
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Traceback (most recent call last):
  File "/home/chrome-bot/.cache/.vpython-root/store/cpython+tkj8tpr2n0oj8m0t270p0m71s0/contents/lib/python3.8/unittest/case.py", line 60, in testPartExecutor
    yield
  File "/home/chrome-bot/.cache/.vpython-root/store/cpython+tkj8tpr2n0oj8m0t270p0m71s0/contents/lib/python3.8/unittest/case.py", line 676, in run
    self._callTestMethod(testMethod)
  File "/home/chrome-bot/.cache/.vpython-root/store/cpython+tkj8tpr2n0oj8m0t270p0m71s0/contents/lib/python3.8/unittest/case.py", line 633, in _callTestMethod
    method()
  File "/b/s/w/ir/x/w/install/emscripten/test/common.py", line 330, in decorated
    f(self, *args, **kwargs)
  File "/b/s/w/ir/x/w/install/emscripten/test/test_core.py", line 2522, in test_pthread_nested_work_queue
    self.do_run_in_out_file_test('pthread/test_pthread_nested_work_queue.c')
  File "/b/s/w/ir/x/w/install/emscripten/test/common.py", line 1777, in do_run_in_out_file_test
    output = self._build_and_run(srcfile, expected, **kwargs)
  File "/b/s/w/ir/x/w/install/emscripten/test/common.py", line 1815, in _build_and_run
    js_output = self.run_js(js_file, engine, args,
  File "/b/s/w/ir/x/w/install/emscripten/test/common.py", line 1404, in run_js
    raise timeout_error
  File "/b/s/w/ir/x/w/install/emscripten/test/common.py", line 1373, in run_js
    jsrun.run_js(filename, engine, args,
  File "/b/s/w/ir/x/w/install/emscripten/test/jsrun.py", line 102, in run_js
    proc = subprocess.run(
  File "/home/chrome-bot/.cache/.vpython-root/store/cpython+tkj8tpr2n0oj8m0t270p0m71s0/contents/lib/python3.8/subprocess.py", line 495, in run
    stdout, stderr = process.communicate(input, timeout=timeout)
  File "/home/chrome-bot/.cache/.vpython-root/store/cpython+tkj8tpr2n0oj8m0t270p0m71s0/contents/lib/python3.8/subprocess.py", line 1028, in communicate
    stdout, stderr = self._communicate(input, endtime, timeout)
  File "/home/chrome-bot/.cache/.vpython-root/store/cpython+tkj8tpr2n0oj8m0t270p0m71s0/contents/lib/python3.8/subprocess.py", line 1894, in _communicate
    self.wait(timeout=self._remaining_time(endtime))
  File "/home/chrome-bot/.cache/.vpython-root/store/cpython+tkj8tpr2n0oj8m0t270p0m71s0/contents/lib/python3.8/subprocess.py", line 1083, in wait
    return self._wait(timeout=timeout)
  File "/home/chrome-bot/.cache/.vpython-root/store/cpython+tkj8tpr2n0oj8m0t270p0m71s0/contents/lib/python3.8/subprocess.py", line 1798, in _wait
    raise TimeoutExpired(self.args, timeout)
subprocess.TimeoutExpired: Command '['/b/s/w/ir/cache/builder/emscripten-releases/node-v20.14.0-linux-x64/bin/node', '--stack-trace-limit=50', '--trace-uncaught', '/b/s/w/ir/x/t/emtest_8v4uhk1t/emscripten_test_cores_czw2q07g/test_pthread_nested_work_queue.js']' timed out after 299.9998672489992 seconds