Concurrency examples are inconsistent with English text around them

[strugee]

Code of Conduct

• [X] I have read and agree to the GitHub Docs project's Code of Conduct

What article on docs.github.com is affected?

https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#concurrency

What part(s) of the article would you like to see updated?

This section is just generally very confusing; see this issue's title. Every example uses group: and cancel-in-progress:. However, the latter isn't even supposed to be introduced - AFAICT - until the section labeled "Example: Using concurrency to cancel any in-progress job or run". It's extremely confusing that the first example uses both of these keys but they haven't been introduced yet. As another example, one of the examples talks about specifying concurrency: ci-${{ github.ref }}, and then the following example does not use this expression - it uses group: ci-${{ github.ref }}.

Additional information

No response