Fix website code highlighting

[clemyan]

What's the problem this PR addresses?

Some code blocks on the website were not highlighted correctly

How did you fix it?

• Added used languages to Docusaurus config
• Fixed some language names on code blocks
  • Turns out yml vs yaml doesn't matter but consistency is always nice

Checklist

• [x] I have read the Contributing Guide.

• [x] I have set the packages that need to be released for my changes to be effective.

• [x] I will check that all automated PR checks pass before the PR gets reviewed.