Docs pages publishing instructions or module

[JohannesRudolph]

We should include instructions somewhere on how to best automate documentation publishing pipelines.

likvid-bank/likvid-cloudfoundation#13 for example added a workflow using terraform state storage on Azure and building on GitHub actions. This is probably not easy to deliver as a standard module because

• has two axis of variation, a) which state storage system you use and b) which CI/CD platform is used
• needs changes to quite a few different places in a collie repository to work (platform.hcl, bootstrap modules, adding a workflow file)

This is why this probably best delivered as a how-to guide in the docs

[florianow]

@JohannesRudolph little bit oudated because we decided support azure and github actions by default as an example. I can add some infos for readme of the bootstrap kit.

[florianow]

#145