Highlight.js throwing `global is not defined` error via `core.js`

### Describe Your Environment

What version of Spectacle are you using? 8.3.0
What version of React are you using? 17.0.13
What browser are you using? Chrome (up to date)
What machine are you on? Mac

### Describe the Problem

I'm trying to bundle a set of similar slide decks for the web using Vite (for guests to visit later, to download references, etc). But I've hit the following error:

```
core.js:221 Uncaught ReferenceError: global is not defined
at capture (core.js:221)
at node_modules/refractor/core.js (core.js:5)
at __require (chunk-4YJPEX7N.js?v=66018443:9)
at hljs.js:891
```

As you can see, it's core.js, called via highlight.js. If you run the app without importing spectacle (e.g. plain react), it works fine.

Here's the test repo:
https://github.com/mikestopcontinues/slides

**Expected behavior:** I should work.
**Actual behavior:** It doesn't work. ;)

### Additional Information

Because syntax highlighting takes up so much darn space in the repo, I think it should be offered as a separate install anyway.