Tree path array 
by Neil Richter @noook
Create a type `Path` that represents validates a possible path of a tree under the form of an array.
Related challenges:
- [Object key path](https://github.com/type-challenges/type-challenges/blob/main/questions/07258-hard-object-key-paths/README.md)
```ts
declare const example: {
foo: {
bar: {
a: string;
};
baz: {
b: number
c: number
}
};
}
// Possible solutions:
// []
// ['foo']
// ['foo', 'bar']
// ['foo', 'bar', 'a']
// ['foo', 'baz']
// ['foo', 'baz', 'b']
// ['foo', 'baz', 'c']
```
