[Chore] Increase test coverage

[olivierobert]

Issue

Automated tests do not sufficiently cover the core business logic of scraping.

Expected

While 100% test coverage is not required for this code challenge, all critical paths of the application should be unit-tested (and, ideally, UI-tested). So the following should be better covered:

• Keyword creation
• Keyword scraping
• Keyword listing

Note

Writing tests for a class that makes a network request is challenging, that is why it an expectation from our side to assess how you approach such a technical challenge.