feat(Navigation): Remove top bar reference

What does this MR do?

The navigation no longer has a top bar with the elements that are described. This change removes this content to avoid confusion.

Does this MR meet the acceptance criteria?

• The MR title and commit messages meet the Pajamas commit conventions.
• The “What does this MR do?” section in the MR description is filled out, explaining the reasons for and scope of the proposed changes, per “Say why not just what”.
  • For example, if the MR is focused on usage guidelines, addressing accessibility challenges could be added in a separate MR.
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Related #1501 (closed)