[PM-8814] Remove EU feature flag

[andrebispo5]

Type of change

• [X] Bug fix
• [ ] New feature development
• [ ] Tech debt (refactoring, code cleanup, dependency upgrades, etc)
• [ ] Build/deploy pipeline (DevOps)
• [ ] Other

Objective

Remove Display EU environment feature flag that is already removed from the server.

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• Please add unit tests where it makes sense to do so (encouraged but not required)
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