Documentation preview in pull requests

[kolyshkin]

Some github repos have mechanisms to show documentation preview in PRs, so that if any documentation is changed, a reviewer can see how it looks like. One such example is https://github.com/docker/docker.github.io (see e.g. docker/docs/pull/11476), implemented via netlify.

We need something like this, too.

Cc @thaJeztah

[thaJeztah]

Not sure if something like that exists for godoc. We could of course run godoc ourselves, and save it somewhere, idk

[kolyshkin]

We can use Github actions and publish artifacts. Let me see...

[kolyshkin]

Made an attempt but failed: #63

We need something like netlify for this, github actions is not adequate.