Loading saved images with stretched config doesn't work

Try passing this object in the `data` field when the constructor is called with `const editor = new EditorJS({}))`

```json
{
"time": 1600668389224,
"blocks": [
{
"type": "image",
"data": {
"url": "https://cdn.pixabay.com/photo/2017/09/01/21/53/blue-2705642_1280.jpg",
"caption": "Here is a caption field",
"withBorder": false,
"withBackground": true,
"stretched": false
}
},
{
"type": "paragraph",
"data": {
"text": "hellow orld"
}
},
{
"type": "paragraph",
"data": {
"text": "hello world"
}
},
{
"type": "image",
"data": {
"url": "https://cdn.pixabay.com/photo/2017/09/01/21/53/blue-2705642_1280.jpg",
"caption": "adsad",
"withBorder": false,
"withBackground": false,
"stretched": true
}
}
],
"version": "2.18.0"
}
```

The third block, i.e. paragraph ' hello world ' will get the `ce-block--stretched` class applied to it and the image below it won't.

But, the settings icon for stretched is toggled. Other settings work fine.

What's the issue?

Reproduce el problema creando una instancia de EditorJS con el objeto de datos proporcionado y comprobando los bloques renderizados. Inspecciona cómo el bloque de imagen gestiona su configuración stretched y compárala con el párrafo que recibe la clase ce-block--stretched; se considera hecho cuando la imagen con stretched: true recibe el estilo stretched esperado sin afectar a otro bloque.

Escrito por el modelo de indexación a partir del texto del issue.