Fix typographical error

[AnayoOleru]

Fixed a typographical error on the publishing-docker-images.md documentation

Why:

Typographical errors could give a different meaning to the reader from the intended meaning behind the sentence. So this PR makes a very simple change to a misprint found when reading through the docs.

What's being changed:

A certain word in a sentence in the https://docs.github.com/en/free-pro-team@latest/actions/guides/publishing-docker-images, under options, required for Docker Hub.

Check off the following:

• All of the tests are passing.
• I have reviewed my changes in staging.
• For content changes, I have reviewed the localization checklist
• For content changes, I have reviewed the Content style guide for GitHub Docs.

[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.

[shati-patel]

Thank you for taking the time to fix the error! Much appreciated 😄 I'll get this change merged shortly 🎉

[github-actions]

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