Spelling issue in Largest Series Product

[meatball133]

On a test the code is suppose to raise following error:

  xit('rejects negative span', () => {
    expect(() => largestProduct('12345', -1)).toThrow(
      new Error('Span must be greater than zero')
    )
  })

While it should only raise on negative values, therefore the error its raising should be: "Span must be greater or equal to zero"