Update reference generation/preview instructions to new p5.js 2.0 fork workflow

[perminder-17]

Current documentation still talks about the old way of generating & previewing the reference (i.e. running npm run docs / npm run docs:dev inside the p5.js repo). Here's how it looks. In p5.js 2.x the workflow has changed: to preview changes you now build the reference from your branch via the p5.js-website repo using npm run custom:dev, and then clean up with npm run custom:cleanup. The old instructions are confusing for contributors working on reference changes. Here's the small description ; https://github.com/processing/p5.js-website/blob/main/docs/scripts.md#testing-the-docs-of-your-fork.

In the PR you can : Replace/update the outdated section about “Generating and previewing the reference” with the updated 2.0 workflow. Here

[adi-ray]

Hi, I would like to take up this issue!

[perminder-17]

Assigned ;)