Exercise 08 - Test failing with solution

[cesarnml]

Steps to reproduce:

1. Copy 08-add-to-window.solution.ts to 08-add-to-window.problem.ts
2. Run npm run exercise 08

Test will fail with following error:

In addition, the greeting returned doesn't match the test expectation.

window.makeGreetingSolution = () => 'Hello!'

it('Should let you call makeGreetingSolution from the window object', () => {
  expect(window.makeGreetingSolution()).toBe('Hello, world!')