title: CakePHP 3 - beforeSave callback not working on edit
body: <p>I have a <code>beforeSave</code>-callback which is called just fine whenever I create a new entity. However when I am editing, it's not called at all.
  Could not find anything in the documentation that could be helpful.</p>
  
  <p>Here's my edit function:</p>
  
  <pre><code>public function edit($id = null) {
      if (!$id) {
          throw new NotFoundException(__('Invalid article'));
      }
  
      $article = $this-&gt;Articles-&gt;get($id);
      if ($this-&gt;request-&gt;is(['post', 'put'])) {
          $this-&gt;Articles-&gt;patchEntity($article, $this-&gt;request-&gt;data);
          if ($this-&gt;Articles-&gt;save($article)) {
              $this-&gt;Flash-&gt;success(__('Your article has been updated.'));
              return $this-&gt;redirect(['action' =&gt; 'index']);
          }
          $this-&gt;Flash-&gt;error(__('Unable to update your article.'));
      }
  
      $this-&gt;set('article', $article);
  } 
  </code></pre>