[CC-000] Adjust upl config url validation due upl api response changes.

[Ryouzanpaku]

No description provided.

[Copilot]

Pull Request Overview

This PR updates the Paylater Invoice configuration URL validation logic in response to changes in the UPL API response format. Instead of asserting exact URL matches, the tests now validate that configuration URLs start with the expected domain prefix.

• Removed hardcoded expected config URLs from test cases
• Changed validation from exact URL equality to domain prefix validation
• Added constant for UPL config domain URL

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