cluster: use kEmptyObject

PR-URL: #43159
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Antoine du Hamel <duhamelantoine1995@gmail.com>

Author: LiviaMedeiros

lib/internal/cluster/worker.js

@@ -7,6 +7,8 @@ const {
 
 const EventEmitter = require('events');
 
+const { kEmptyObject } = require('internal/util');
+
 module.exports = Worker;
 
 // Common Worker implementation shared between the cluster primary and workers.
@@ -17,7 +19,7 @@ function Worker(options) {
   ReflectApply(EventEmitter, this, []);
 
   if (options === null || typeof options !== 'object')
-    options = {};
+    options = kEmptyObject;
 
   this.exitedAfterDisconnect = undefined;