Add instruction on how to use older versions of docs

[asvae]

Some users want to stay on older versions and need docs for older versions.

We only host latest version, which is something we don't want to change right now.

But we can definitely provide instructions on how to run these locally.

See #3887, I had instructions laid down there already.

[m0ksem]

How about we build it locally before release and store somewhere on github pages? Glad we use SSG for it, So we can host static files in this hierarchy:

- 📂1.7.6
  - 📁 ui-elements
  - 📁 introduction
  ...
  - 📃 index.html
- 1.6.4
  - 📁 ui-elements
  - 📁 introduction
  ...
  - 📃 index.html

Then use redirect https://archive.vuestic.dev/1.7.6 -> https://epicmaxco.github.io/archive or show it in iframe. idk.

I would make it manually deployed, not automated.