Remote Hosted Code causing extension review rejection

### Description

Some third party code is causing google to reject any extensions using model-viewer, exact message:

Thank you for reaching out to us. As conveyed in the previous mail, your item was rejected for not being compliant with the “Remote Hosted Code” policy. We could see remote hosted code in the dist/521.58e8cce0df2779ab.js file where it is fetching code from an external domain (https://cdn.jsdelivr.net/npm/three@0.149.0/examples/jsm/loaders/LottieLoader.js )

Inlining this code would be better, thanks.

#### Live Demo
N/A

### Version
- model-viewer: v3.3.0

### Browser Affected
- [ x] Chrome
- [ ] Edge
- [ ] Firefox
- [ ] IE
- [ ] Safari

### OS

- [x ] Android
- [ x] iOS
- [ x] Linux
- [ x] MacOS
- [ x] Windows