Add guidance for hosting on Render

[fofr]

Render is one of the hosting providers that the prototype kit now recommends:
https://govuk-prototype-kit.herokuapp.com/docs/publishing

This is render:
https://render.com/

It has a free tier with persistent access for static sites or 15min spin-down for web services:
https://render.com/docs/free

Deploying a static site is pretty simple.
Deploying a password protected design history using a web service is a little more involved.

[frankieroberto]

I wonder if we should include guidance for publishing with GitHub pages, and possibly Netlify?

Do we need to mention setting it up with a password at all, or can we assume/recommend that these are all public?

[fofr]

Netlify guidance is already there, but maybe a little hidden.