Update documentation to use inclusive language, gender neutral name and pronoun.

What does this MR do?

Removes the name "John" and pronoun "his" from this documentation page.

Aligns with our value of Diversity and inclusive language from https://about.gitlab.com/handbook/values/#diversity.

Inclusive language In our general guidelines we list: 'Use inclusive language. For example, prefer "Hi everybody" or "Hi people" to "Hi guys".

Inspired & improved by @tipyn

Are there points in the code the reviewer needs to double check?

Why was this MR needed?

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests added for this feature/bug
• Review
  • Has been reviewed by UX
  • Has been reviewed by Frontend
  • Has been reviewed by Backend
  • Has been reviewed by Database
• EE specific content should be in the top level /ee folder
• Conform by the merge request performance guides
• Conform by the style guides
• Squashed related commits together
• Internationalization required/considered
• If paid feature, have we considered GitLab.com plan and how it works for groups and is there a design for promoting it to users who aren't on the correct plan
• End-to-end tests pass (package-qa manual pipeline job)

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