title: Array.includes always false javascript
body: <p>I have the following object</p>
  
  <pre><code>{ _id: 58ae39c54473f9cfd4eb29b6,
    email: 'another@club.com',
    name: 'Another Club Renamed',
    __v: 0,
    createdEvents: [],
    instructors: [ 58a5ac4f84230a2117d1d6cb, 111111111111111111111111 ],
    members: [] }
  </code></pre>
  
  <p>when I use the method</p>
  
  <p><code>object.instructors.includes(58a5ac4f84230a2117d1d6cb)</code>
  <code>object.instructors.includes(111111111111111111111111)</code></p>
  
  <p>or </p>
  
  <p><code>object.instructors.includes('58a5ac4f84230a2117d1d6cb')</code>
  <code>object.instructors.includes("111111111111111111111111")</code></p>
  
  <p>the result is always false am I doing something incorrect?</p>
  
  <p><code>Array.isArray(club.instructors)</code> returns true</p>
  
  <p>EDIT: The object is a <code>mongoose.document</code>. The object above is exactly how it gets logged to the console when I execute</p>
  
  <pre><code>Club.findById(id (err, club) =&gt;{
      console.log(club);
  })
  </code></pre>