title: Javascript move object key to parent object key
body: <p>I have a question related to javascript objects. </p>
  
  <p>I have an object like this:</p>
  
  <pre><code>const event = {
    title: 'some event',
    start: {
      date: '2019-04-16 12:33:04'
    }
  }
  </code></pre>
  
  <p>You see that there is another object in the start key. Now my question; how can I move that value to just only the start key? So that i have something like this:</p>
  
  <pre><code>const event = {
    title: 'some event'
    start: '2019-04-16 12:33:04'
  }
  </code></pre>
  
  <p>Thanks!</p>
  
  <p>EDIT
  I'm was not clear enough about my question:</p>
  
  <p>So i have an api request with axios: </p>
  
  <pre><code>axios.get(url).then(res =&gt; {
    // The result is an array of objects and I want to map every start.date to just start
  });
  </code></pre>