Add margin/padding support to Archives block

[tellthemachines]

What?

Addresses part of #43243.

Why?

For consistency of design tools between blocks.

How?

Adds margin and padding supports to Archives block.

Testing Instructions

1. Add an Archives block to a post;
2. Check that margin/padding controls are available in the block sidebar;
3. Change the values for margin and padding and check they work as expected on editor and front end.

Screenshots or screencast

[carolinan]

Tested with the spacing scale in TT3. The controls do not look the same to me as in the screenshot, instead, I see the select list. I believe that is expected since the values in the theme are custom?