adds options for 3 or 4 items in box links listing

[markconroy]

Closes #886

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Thanks to Big Blue Door for sponsoring my time to work on this.

[finnlewis]

Note: this will only have an effect we merge localgovdrupal/localgov_paragraphs#267

@tonypaulbarker asks about update hooks, at the mo this has none.

Maybe just release notes to clarify.

[finnlewis]

Thanks @markconroy !
The layout options seem to work as expected.

1 col

2 per row

3 per row

4 per row

[finnlewis]

@markconroy I noted on the 3 per row example, that the spacing between the rows was a little different to the follow us links below. I think this is because they are using flex rather than grid, so the calculations are a little different, is that right?

[markconroy]

@finnlewis it's because those box links are not a "box links" (plural) component. They are 3 individual box links in a 3-column layout. And our 3-column layouts are not using grid just yet.

[tonypaulbarker]

@finnlewis @markconroy in the drag and drop editor of a subsite overview these don't have any spacing between them in the edit window so the settings don't appear to make any difference until its rendered on the front end. I think we should add some styles to localgov_admin_theme_improvements to handle the case because it might confuse editors.

When I choose 'two per row' and I have three links it still displays three side by side in the editor, and I get some padding.

[markconroy]

@tonypaulbarker if you want that spacing to appear on the backend, it might be best to add the CSS into the localgov_paragraphs module.

But then we'll have the question, "should we do this for all CSS?".

I think it's okay to have an 'admin experience' which focusses on content and as frontend experience which deals with design.