Fibonacci Sequence
by windliang @wind-liang
Implement a generic `Fibonacci` that takes a number `T` and returns its corresponding [Fibonacci number](https://en.wikipedia.org/wiki/Fibonacci_number).
The sequence starts:
1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, ...
For example
```ts
type Result1 = Fibonacci<3> // 2
type Result2 = Fibonacci<8> // 21
```