Note case-sensitivity of CODEOWERS in CODEOWNERS syntax docs

[chrisgarber]

Why:

Closes#12760

What's being changed:

Copy on https://docs.github.com/en/repositories/managing-your-repositorys-settings-and-features/customizing-your-repository/about-code-owners. See auto-comment for staging links for a "live" view.

In addition to the proposed case sensitivity changes, there were two example sections that covered similar content. I combined the two examples into one block.

Check off the following:

• I have reviewed my changes in staging (look for "Automatically generated comment" and click Modified to view your latest changes).
• For content changes, I have completed the self-review checklist.

Writer impact (This section is for GitHub staff members only):

• This pull request impacts the contribution experience
  • I have added the 'writer impact' label
  • I have added a description and/or a video demo of the changes below (e.g. a "before and after video")

[welcome]

Thanks for opening this pull request! A GitHub docs team member should be by to give feedback soon. In the meantime, please check out the contributing guidelines.

[github-actions]

Automatically generated comment ℹ️

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The table contains an overview of files in the content directory that have been changed in this pull request. It's provided to make it easy to review your changes on the staging site. Please note that changes to the data directory will not show up in this table.

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Content directory changes

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Source	Staging	Production	What Changed
content/repositories/managing-your-repositorys-settings-and-features/customizing-your-repository/about-code-owners.md	Modified	Original

[ramyaparimi]

@chrisgarber
Thanks so much for opening a PR! I'll get this triaged for review ⚡

[chrisgarber]

Anything I can do to help move this through?

[ramyaparimi]

@chrisgarber Our small team is working our way through reviewing all of the amazing contributions that were made during the holidays ✨ One of the writers would be reviewing this PR soon. Thanks for your patience!

[chrisgarber]

sounds good, thanks for your hard work 👍

[ethanpalm]

Thanks for creating this PR, @chrisgarber! Your changes look great. I've just made a few small changes to the syntax (for example instead of e.g.) and to use a liquid reusable for GitHub.

Thank you for contributing to the GitHub docs and helping clear things up around case sensitivity for CODEOWNERS files ✨

[github-actions]

Thanks very much for contributing! Your pull request has been merged 🎉 You should see your changes appear on the site in approximately 24 hours. If you're looking for your next contribution, check out our help wanted issues ⚡