Docs unclear

[LarsKue]

The demo suggests to create a pull request at the end of each step, but is a little bit unclear on where exactly this request should be created. I would suggest changing the wording to the following:

Create a pull request on GitHub and merge the changes from branch step0 into your fork's main branch.

Judging by all the auto-closed PR's on this repo, I am not the only one who was unsure if they should create a PR to the main repo.