Add sections to editor-setup about Prettier and ESLint

[Princesseuh]

What kind of changes does this PR include?

• Minor content fixes (broken links, typos, etc.)
• New or updated content
• Translated content
• Changes to the docs site code
• Something else!

Description

Added a section to the Editor Setup page about how to setup Prettier and ESLint.

For ESLint, I opted to simply link the the plugin's User Guide. My reasoning being that being an unofficial plugin, changes might change the installation / configuration process without us noticing. (And it shouldn't be the burden of the community members maintaining it to update our docs, in my opinion.)

For Prettier, I documented how to install it and use it in a CLI scenario in our docs and left a link to the README for further information on how to use it in VS Code and possible settings. I however documented how to make it work in pnpm because it's an issue people encounter very very frequently, to the point where people often think the plugin is broken

This PR also fix a slight mistake in the remote url inside CONTRIBUTING.md

Fix #425

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[delucis]

Thanks so much for this @Princesseuh — this is really great. I’ve made some minor suggestions — mostly just punctuation or small style nits, but otherwise this LGTM! 💜

[delucis]

Thanks Erika. Couple of more suggestions based on Sarah’s feedback and then you should be good to merge!