feat(comments): add docs for markdown comments

[tay1orjones]

We've had a few content contributors to our site ask about how to insert comments on the markdown pages. This adds some lightweight docs to the markdown section

Changelog

New

• Add Comments section to markdown examples page

Changed

• I think prettier caused the single -> double quote formatting changes

[vercel]

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[vpicone]

Thanks, @tay1orjones!! Would welcome any other markdown tips you or your team want to publish. Sometimes I take these things for granted.