docs: update markdown docs

[alisonjoseph]

Adds a note to card component pages about warning about whitespace.
Updates formatting in examples (had to turn off prettier to get this to not format, couldn't figure out how to ignore??)

[vercel]

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[vpicone]

For prettier you can either:

<!-- prettier-ignore -->
Do   not    format   this
<!-- prettier-ignore-end -->

Or use md instead of jsx for the language in your codeblock.

[alisonjoseph]

<!-- prettier-ignore-->

doesn't seem to do anything, its still auto-formatting when I save 🤔

[boneskull]

There may be a bug or missing feature or something, see prettier/prettier#5557