No tip offsets after upgrade to 2.x

Problem/Motivation

After upgrading to tour 2.x, tips are squashed against the element they point to, and the arrow overlaps the element. In 1.x, they had a nice margin and the arrow did not overlap the element.

Proposed resolution

The floatingUIOptions declared in TourViewBuilder.php don't work with newer versions of Shepherd.js. Replace them (somehow) with Floating UI middleware. For example, offset.