Option to hide sequoia-component when no #12

For old posts that aren't published, the comments component shows:

No document found. Add a <link rel="site.standard.document" href="at://..."> tag to your page.

It would be great if we could hide this. As a default to show there's potentially a problem it's fine, but maybe a component attribute that basically says: make it display: none (or something) if no <link rel="site.standard.document" /> is found.

See https://github.com/stevedylandev/sequoia/issues/1 for more context.