Code Screenshots are slightly cropped

Bug Template

Describe the bug
When you create an image of your code, the blocks on the edge are all a little cropped.
It's not that much visible, but when you try to upscale the images you will see it.

Based on the documentation at https://makecode.microbit.org/blocks-embed we made a little tool to help teacher to create images for their materials. This tool has an upscaling function and the posibility to export SVG and makes the issue more visible: https://go.calliope.cc/tools/makecode/codeimages/ (it's german, but pretty straight forward and everyone's welcome to contribute and translate).

To Reproduce
Steps to reproduce the behavior:

1. Create some Blocks
2. Right click
3. Create screenshot of code
4. Check the edges of the image

Expected behavior
The image canvas should be slightly bigger to cover the full block.

Screenshots

Start from the block editor's “Create screenshot of code” action described in the issue and compare the canvas bounds with blocks at each edge. Reproduce the listed steps and consult the linked blocks-embed documentation; done when full edge blocks appear without cropping, including after upscaling and SVG export.