Does not work with JSDom

[aendra-rininsland]

Currently g-axis makes a lot of calls to SVGElement.getBBox(), which JSDom cannot do anything with because it doesn't do any visual calculations.

There are two ways to resolve this:

1. Explicitly not support JSDom implementations

I'd prefer not to do this if possible because it would mean needing to use really heavy implementations like PhantomJS or Puppeteer on the server, which will reduce adoption of using the charts programmatically within the org.

2. Find a better, non-getBBox() way of calculating sizes

d3-axis seems to manage this fine, it works in JSDom and headless contexts.