* Check for migrated username
* Add e2e for reserved username due to migration
* Add username change test
* Update username.ts
* fixed type checks
* Refactor to use isOrganization
* Typing
* Typing
* Removed the isOrganization function
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Co-authored-by: Joe Au-Yeung <65426560+joeauyeung@users.noreply.github.com>
Co-authored-by: Keith Williams <keithwillcode@gmail.com>