Improve Select Menu spacing

[shawnbot]

It's funny, but I find myself being really bothered by the spacing of our new Select Menu (introduced in #808) items when looking at a menu in isolation (top). What if we normalized the header and item padding (bottom)? Or could we allow folks to opt in to this layout when they're using check octicons rather than it being the default?

This bothers me a lot less, but there's still the issue of our button padding not being in our whitespace scale (6px). 🙃

[simurai]

Or could we allow folks to opt in to this layout when they're using check octicons rather than it being the default?

👍 Yeah, that would definitely look better when no check icons are used. Here a PR #844.

Still have to look into the best way of removing the "white space gap". #844 (comment)

[shawnbot]

Still have to look into the best way of removing the "white space gap". #844 (comment)

We might want to consider using flexbox for the horizontal layout. That would allow the text alongside the checkbox to wrap more elegantly, right?