Clean up logged_out_marketing_header

Related to [Experiment Cleanup] Create a marketing header ... (#364487 - closed)

What does this MR do and why?

This was run as an experiment. Was rolled out to 50%. The header had small UX issues. After fixing issues, the changes need to become an official part of the product.

Note as part of this clean up we should improve the CSS as the nav bar scales down in size so the list items collapse causing the nav bar to increase in height.

Screenshots or screen recordings

https://drive.google.com/file/d/1NQ7dq5j8iSBY6qMMDorI5PZ3srlyz9Ih/view?usp=sharing

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