Add YAML description meta tags

[guimachiavelli]

Fixes #2573

[github-actions]

All broken links are now fixed, thank you!

[qdequele]

Hello @guimachiavelli it's great! Is it also possible to add the titles? I did it in my test PR. https://github.com/meilisearch/documentation/pull/2571/files

[guimachiavelli]

Hi @qdequele! My plan is to address the titles programmatically, as the majority should really be [Page's H1] — Meilisearch documentation. So, for example, the page title for the cloud getting started would be Getting started with Meilisearch Cloud — Meilisearch documentation. I'm looking into how to do that, but I believe we might be able to skip basement.

[guimachiavelli]

After some research, <title>s were not implemented in a way we can easily and safely customise. Skipping basement and doing it ourselves does not look like a good choice.

Taking in consideration the time it will take for basement to do this, though, I have manually edited the <title> for each documentation page.

At a later date, once they're done with our current requests, we'll investigate how we can properly automate this.

[qdequele]

LGTM