Migrate BrowserRouter to MemoryRouter in 2 remaining test files

[arbrandes]

Context

PR #1641 review noted that the PR correctly migrated most test files from BrowserRouter to MemoryRouter, which is React Router's recommended approach for unit tests (keeps location changes in memory without touching the browser's history API). Two test files were not part of the PR's scope and still use BrowserRouter.

Files

1. src/common-components/tests/EmbeddedRegistrationRoute.test.jsx

• 2 BrowserRouter usages (1 import, 1 render wrapper)
• Replace with MemoryRouter and pass initialEntries as needed

2. src/common-components/tests/UnAuthOnlyRoute.test.jsx

• 2 BrowserRouter usages (1 import, 1 render wrapper)
• Replace with MemoryRouter and pass initialEntries as needed

Migration pattern

Each file will:

1. Replace import { BrowserRouter } with import { MemoryRouter } from react-router-dom
2. Replace <BrowserRouter> wrapper with <MemoryRouter initialEntries={['/path']}> using the appropriate test route