Adds less-modules reference

[katrotz]

Awesome Contribution Checklist:

• [x] I have read, and re-read the Contributing Guidelines
• [x] I have searched to ensure the suggested item doesn't exist on this list
• [x] This PR contains only one item

Please Describe Your Addition

Added the reference to the less-modules rollup plugin.

[shellscape]

Cheers 🍻