wip Gm 366 app header dropdown

[thedoomshine]

Overview

PR Checklist

• [ ] Related to designs:
• [ ] Related to JIRA ticket: ABC-123
• [ ] I have run this code to verify it works
• [ ] This PR includes unit tests for the code change

[CLAassistant]

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11 out of 12 committers have signed the CLA.

:white_check_mark: codecademy-gh-api
:white_check_mark: timjenkins
:white_check_mark: dreamwasp
:white_check_mark: aresnik11
:white_check_mark: borisonr
:white_check_mark: aionate0812
:white_check_mark: ahmed-abdallah
:white_check_mark: thedoomshine
:white_check_mark: codecaaron
:white_check_mark: natalieweesh
:white_check_mark: jcenglish
:x: Yaron Shahverdi

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