Fix ERR_INVALID_ARG_TYPE on Node.js nightly

[aduh95]

This PR fixes a bug that currently happen on nightly versions of Node.js due to a recent in the Node.js codebase:

1) WorkerHandler
       create a worker handler with custom script:
     Uncaught TypeError [ERR_INVALID_ARG_TYPE]: The "options" argument must be of type object. Received an instance of Array
      at ChildProcess.target.send (node:internal/child_process:716:7)
      at Array.forEach (<anonymous>)
      at dispatchQueuedRequests (src/WorkerHandler.js:262:21)
      at ChildProcess.<anonymous> (src/WorkerHandler.js:221:7)
      at ChildProcess.emit (node:events:378:20)
      at emit (node:internal/child_process:920:12)
      at processTicksAndRejections (node:internal/process/task_queues:82:21)

  2) WorkerHandler
       should handle the asynchronous initialization of a worker:
     Uncaught TypeError [ERR_INVALID_ARG_TYPE]: The "options" argument must be of type object. Received an instance of Array
      at ChildProcess.target.send (node:internal/child_process:716:7)
      at Array.forEach (<anonymous>)
      at dispatchQueuedRequests (src/WorkerHandler.js:262:21)
      at ChildProcess.<anonymous> (src/WorkerHandler.js:221:7)
      at ChildProcess.emit (node:events:378:20)
      at emit (node:internal/child_process:920:12)
      at processTicksAndRejections (node:internal/process/task_queues:82:21)

  3) Main Thread Detection
       should detect isMainThread in child_process:
     Uncaught TypeError [ERR_INVALID_ARG_TYPE]: The "options" argument must be of type object. Received an instance of Array
      at ChildProcess.target.send (node:internal/child_process:716:7)
      at Array.forEach (<anonymous>)
      at dispatchQueuedRequests (src/WorkerHandler.js:262:21)
      at ChildProcess.<anonymous> (src/WorkerHandler.js:221:7)
      at ChildProcess.emit (node:events:378:20)
      at emit (node:internal/child_process:920:12)
      at processTicksAndRejections (node:internal/process/task_queues:82:21)

Refs: https://github.com/nodejs/node/pull/37028/files#r566771229

[josdejong]

Thanks for this fix Antoine!

[josdejong]

Your fix is published now in v6.1.0. Thanks again!