Update highlight.js to v11.11.1

[XhmikosR]

Languages included:

• json
• plaintext

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I'm not sure which languages are used. I mainly see JSON, one instance of HTML and one plaintext.

The HTML and plaintext snippets are not highlighted on develop nor here for me, though so this means it's another issue.

Note that this fixes a console error regarding exports which makes me wonder how this even worked before... Is this even used?

Uncaught SyntaxError: export declarations may only appear at top level of a module

I only tested this by spinning a local server in the docs path.

EDIT: I added a second patch which remove highlight.js. If everything looks good let me know so that I squash the patches.

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[XhmikosR]

@DL6ER can you confirm if highlight.js is really needed?

It's one less external dependency if not, otherwise the first patch does fix highlight.js loading, which is another reason I suspect that highlight.js is unused since it wasn't being loaded before this patch due to the SyntaxError.