chore: add some redirects to v1.docusaurus.io

[slorber]

Motivation

SEO tools report we have a few external links targeting Docusaurus v1 URLs, but these links now show a v2 404 page.

We can:

• redirect those URLs to the v1.docusaurus.io subdomain (same page)
• redirect those URLs to the v2 homepage (v1 pages might not exist in v2) and try to pass the "SEO juice" to v2

I choose the first solution

[github-actions]

Size Change: 0 B

Total Size: 631 kB

ℹ️ View Unchanged

Filename	Size	Change
website/build/assets/css/styles.********.css	88 kB	0 B
website/build/assets/js/main.********.js	453 kB	0 B
website/build/blog/2017/12/14/introducing-docusaurus/index.html	62.3 kB	0 B
website/build/docs/introduction/index.html	235 B	0 B
website/build/index.html	27.1 kB	0 B

_{compressed-size-action}

[netlify]

[V2]

Built with commit 776b5e7

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[netlify]

[V1]

Built with commit 776b5e7

https://deploy-preview-4670--docusaurus-1.netlify.app