Menus should use Bootstrap nav/nav-link only for horizontal menus in header region

Problem/Motivation

Nav links really work well for horizontal navigation, for example for primary and secondary and any other menu links in the header. For footer, they do not look that good because they occupy a lot of vertical space (because of vertical padding) and also they are adding horizontal padding which does not look good because of the grid, this is the reason we created #3186903: Improve footer links on mobile where we reset horizontal padding.

Ideally, we should use nav links only for horizontal menus in the header, for all other menus (they are in most cases vertical) we should use regular links.
Check how Bootstrap home page is using links in footer menus (https://getbootstrap.com/), they are using list-unstyled component. This looks much better than nav-links.

Proposed resolution

Use nav links only for header navigation links. For all other menus use list-unstyled component. Also, use h3 for these blocks instead of default h2 which is too big and does not look good in the footer region.