Consider using mkdocs-redirects plugin over Cloudflare redirects

[StevenMaude]

https://github.com/mkdocs/mkdocs-redirects

Advantages

• Configured more explicitly in the MkDocs projects
• Shouldn't have arbitrary redirect failures, as happened in the past with Cloudflare and was to do with the order of redirects
• Shouldn't need to ensure the redirects work, unlike Cloudflare (for which we added an automated GitHub Actions check)
• Independent of the host; so if we move from Cloudflare to something else, we don't need to recreate the redirects.
• Should work in local preview, which the Cloudflare redirects don't.

Disadvantages

• No 301 redirects possible — we do use 301 redirects already, although these are perhaps better avoided anyway, in case you want to reuse the URL and because of persistence in browser caching.