Ch 9 Working With Laziness Exercise 28 Test Bug

[lgtout]

https://github.com/pysaumont/fpinkotlin/blob/d567d767fe8540b3766608730d967a5bf70f0730/fpinkotlin-parent/fpinkotlin-workingwithlaziness-exercises/src/test/kotlin/com/fpinkotlin/workingwithlaziness/exercise28/StreamTest.kt#L17

The test for this exercise may be insufficient because it passes the case where the fibonacci stream produces only zeros.

z + y == x will always be true when z, x, y are 0. But this sequence isn't fibonacci.