Link from pages and footer to a versioned doc

[lorenzolewis]

We are currently using the second method discussed in https://docusaurus.io/docs/versioning#configuring-versioning-behavior so that our "latest" docs are served under a version number (v1 in this scenario).

For navBar items, you can use type: 'doc' to dynamically build the url to the correct doc version. I'm not able to recreate this behaviour for footer items linking to docs. I'm also not seeing how to link to a doc from a page (such as index.js) to the correct "latest" doc url.

[Josh-Cena]

Let's discuss in #7402 instead