Update prerequisites (git, SSH key, ...)

[amanmdesai]

Github also allows for instance using the https (which might be simpler to setup)

Secondly, provide link on how to add ssh key or to use https.

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[enibigir]

This is one of the prerequisites already mentioned in the "Setup" section. I will update the prerequisites.

[klieret]

(I think setup and prerequisites are slightly different: Setup should just be about setting things up, not about learning and understand stuff (that's prerequisites) -- the latter takes potentially more time to complete)

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This issue or pull request has been automatically marked as stale because it has not had recent activity. Please manually close it, if it is no longer relevant, or ask for help or support to help getting it unstuck. Let me bring this to the attention of @klieret @wdconinc @michmx for now.