title: Sequelize Hooks- Previous data values for afterBulkUpdate
body: <p>I am trying to create a hook <code>beforeBulkUpdate</code> and get new and previous values of a field. I tried using <code>.reload()</code> on the model and <code>_previousDataValues</code> but they only work on instances and not bulk create and update (I'm using bulk update). Is there a way to get the previous value of field using the <code>beforeBulkUpdate</code> hook?</p>
  
  <pre><code>beforeBulkUpdate: (person) =&gt; {
    console.log(person.name) // 'John' (new name)
    Person.findOne({ where: { id: input.id } }).then(person =&gt; {
    person.reload().then(() =&gt; {
      console.log(person.name) // 'John' (expected old name, but returns new name)
      })
    })
  }
  </code></pre>