Bug: Stretch stretches the block below

There seems to be some index issue.

**How to reproduce:**

- Add an image via drag & drop to a freshly initialized EditorJS.
- Add some Text block below.
- Now choose stretch from the image menu.

**Result:**
The text block is stretched, instead of the image.

If you move the text block up and do the same again, the image is stretched.

In the demo of the EditorJS website, all works perfectly, but in practice using the latest components, not.