fix(array): fix set() with a path going through an array

[tzi]

When we use set() with a path that contain an array, the array reconstruction can miss some elements.

For example, considering having this base object:

{
  a: {
    b: [{ id: 1, next: 1 }, { id: 2, next: 1 }, { id: 3, next: 1 }, { id: 4, next: 1 }],
  },
};

If we want to update the path a.b.0.next there was no problem, but if we update the path a.b.1.next we lost the thrid and forth elements.

This happens when rebuilding the array. Here is an extract of the library code:

return [
  ...currentBase.slice(0, key),
  set(currentBase[key]),
   ...currentBase.slice(key + 1),
];

In our case, key + 1 is evaluted to 11 since key was a string. So we lost the values from 2 to 10.

My PR add the described test, and a parseInt() to avoid this problem.