[#1833] Update default p5.js to v1.3.1

[catarak]

Fixes #1833

I have verified that this pull request:

• has no linting errors (npm run lint)
• is from a uniquely-named feature branch and has been rebased on top of the latest develop branch. (If I was asked to make more changes, I have made sure to rebase onto develop then too)
• is descriptively named and links to an issue number, i.e. Fixes #123

[release-com]

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• p5.js-web-editor
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🔧Environment Status : https://app.releasehub.com/public/Processing%20Foundation/env-a2d77f38af