Profile layout update

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Note: This is part 5 of a few merge requests targeting profile-layout-reorganization. We're splitting into several in the hopes that it'll be easier to review 🤞

You can see the previous MRs here --> !137024 (merged)

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What does this MR do and why?

• Moved sidebar content to right side
  • Why?
    • More closely matches other pages (project overview, MR, isssuable sidebars) to provide more consistency across GitLab
• Moves avatar + name + username metadata to top header
  • Why?
    • Matches general layout of other pages (project overview, MR, issuables)
    • More similar to our existing layout will mean the changes are less jarring

Screenshots or screen recordings

	Before	After
Full profile
Half filled-out profile
Empty profile

How to set up and validate locally

✂️ UX Paper Cuts 16.7 → Project page (#430244 - closed)

✂️ UX Paper Cuts 16.8 → Accessibility (#424396 - closed)