Object Array Not Updated

controllers.application.js

import Ember from 'ember';
import {set} from '@ember/object';
import { A } from '@ember/array';
export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  apiObj: [
    { arr : ['s']},{ arr : ['s']},{ arr : ['s']}
  				],
  actions: {
  	change(arr,index) {
      this.set('arr',arr);
      let newArr = new Array(arr);
     	newArr.push('g');
      this.set('arr',newArr);
      console.log(this.arr, arr);
    }
  }
});

templates.application.hbs

<h1>Welcome to {{appName}}</h1>
<br>
<br>
{{outlet}}
<br>
<br>
{{#each apiObj as | obj index|}}
	<b {{action "change" obj.arr index}}>{{obj.arr}}</b>

  <br>
{{/each}}

twiddle.json

{
  "version": "0.15.1",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.js",
    "ember": "3.4.3",
    "ember-template-compiler": "3.4.3",
    "ember-testing": "3.4.3"
  },
  "addons": {
    "ember-data": "3.4.2"
  }
}