Columns Block: Provide Gutter Size Control

[iamtakashi]

I often wish the block has gutter size control to make a design like this example.

Currently, this is impossible to do with the column block as it always adds gutters.

I've seen an exploration adding presets like None, S, M, L, but I don't believe that it'd satisfy the various needs, and I personally prefer a fine control similar to the setting added to the Cover block.

[richtabor]

At CoBlocks we're thinking through a component that supports None, S, M, L, and (custom) for sizing controls such as gutter. Our plan is that S, M, L are each CSS variable driven (for consistency across the site design), but that CSS variable can be overwritten with a custom selection.

[talldan]

This looks like a duplicate of #10730