Add necessary files

[ydah]

This PR prepared the necessary files with reference to https://github.com/rubocop/ruby-style-guide .

[bquorning]

I wonder if it wouldn’t be easier to build the gh-pages from GitHub Actions instead of setting it up in Circle CI?

[ydah]

I wonder if it wouldn’t be easier to build the gh-pages from GitHub Actions instead of setting it up in Circle CI?

Once I brought it from another style-guide repository, I thought that improvements could be made later, so I copied it once. OK, I will rewrite it in GHA.

[ydah]

The deployment mechanism was created in GHA with the assumption that the following settings would be made
Generate documents by asciidoctor under docs/ at the timing of push to main. If there is any change, push the change to main. What do you think?

[ydah]

Tested in another repository:
https://github.com/ydah/capybara-style-guide/actions/runs/7486787282/job/20377842663

The following commits were pushed:
ydah@8e50673

[timdiggins]

The deployment mechanism was created in GHA with the assumption that the following settings would be made
Generate documents by asciidoctor under docs/ at the timing of push to main. If there is any change, push the change to main. What do you think?

The other mechanism (the only one I've used before) is to (force)push to gh-pages branch. The advantage of this is that if for some reason some manual (emergency) tweaks are required they can be done.

If this mechanism (pushing to $GITHUB_REF, which I think will be main?) runs when there's a push to main and also pushes to main, it may be that we can't do any manual changes (will github not get stuck in a loop of github actions?)

Sorry I'm a gh actions newbie so I might be on the wrong track