title: Update CkEditor config on the basis of React state
body: <p>I am using <a href="https://github.com/ckeditor/ckeditor5" rel="nofollow noreferrer">CkEditor5</a> for implementing CKEditor in my React application. I want to update the config wrt my state. But it seems like the editor component isn't updating even after the state change.
  Here is my CKEditor component</p>
  
  <pre><code>&lt;CKEditor
      editor={ ClassicEditor }
      data={this.state.content}
      onInit={ editor =&gt; {
          console.log( 'Editor is ready to use!', editor );
      } }
      config={{
        simpleUpload: {
        uploadUrl: uploadUrl,
        headers: {
            'X-CSRFToken': csrftoken,
        }
      }}}
      onChange={ ( event, editor ) =&gt; {
          const data = editor.getData();
          this.setState({
            content: data
          })
          console.log( { event, editor, data } );
      } }
      onBlur={ ( event, editor ) =&gt; {
          console.log( 'Blur.', editor );
      } }
      onFocus={ ( event, editor ) =&gt; {
          console.log( 'Focus.', editor );
      } }
  /&gt;
  </code></pre>
  
  <p>I want to update the upload URL based on the state.
  It is stored in a variable like shown below -</p>
  
  <pre><code>const csrftoken = getCookie('csrftoken');
  const uploadUrl = `https://example.com/api/blog/posts/images/${this.state.id}`
  </code></pre>