Chore/webpack v5

[catarak]

Fixes #2019

Changes:

• Updates webpack from v4 to v5
• Updates most packages that webpack depends on to the latest
• Updates node-sass and async packages, which have security issues

I have verified that this pull request:

• has no linting errors (npm run lint)
• has no test errors (npm run test)
• is from a uniquely-named feature branch and is up to date with the develop branch.
• is descriptively named and links to an issue number, i.e. Fixes #123

[release-com]

Release Environments

This pull request environment is provided by Release, learn more!
To see the status of the environment click on Environment Status below.

• p5.js-web-editor
  • app-tede226-p5-js-web-editor.rls.sh
  • preview-tede226-p5-js-web-editor.rls.sh

🔧Environment Status : https://app.releasehub.com/public/Processing%20Foundation/env-33becab929