Product Image Gallery: placeholder goes outside the block selection

[gigitux]

Describe the bug

On WP 6.2 with the Tsubaki theme enabled, the placeholder of the Product Image Gallery goes outside the block selection:

To reproduce

Steps to reproduce the behavior:

1. Enable the Tsubaki theme
2. Edit the Single Product Template
3. Via code editor, replace the template with this
4. Focus on the Product Image Gallery Block.
5. See that the placeholder goes outside the block selection (as in the image below).

Expected behavior

The placeholder should not go outside the block selection.

Screenshots

[kmanijak]

When editing the page via code editor, there's a glitch: on the narrow screen, the Product Gallery overlaps with the content on the right:

https://user-images.githubusercontent.com/20098064/225862631-b581a8a4-a0a6-43d4-91f5-6d002845ba74.png

It seems Product Gallery doesn't downscale when squeezed by the Column

https://user-images.githubusercontent.com/20098064/225862945-08b5340a-d07f-4506-9eb2-6e048d636d71.png

Found in the scope of #8767