bug(linked-list): `insert` method duplicates value of head in tail

Hi, guys! Thank you for this awesome repository! The other day I found this problem

const list = new List();

list.insert(2, 0);
list.insert(3, 1);
list.insert(4, 2);

returns

{
  "head": {
    "data": 2,
    "next": {
      "data": 3,
      "next": {
        "data": 4,
        "next": null
      }
    }
  },
  "tail": {
    "data": 2,
    "next": {
      "data": 3,
      "next": {
        "data": 4,
        "next": null
      }
    }
  },
}

It solved if you add this code after line 77.

this.tail.next = newNode;
this.tail = newNode;

Start in src/data-structures/linked-list/LinkedList.js around line 77 and reproduce the reported insert sequence. Inspect how head and tail are updated when inserting at the end; done means the tail references the final node rather than duplicating the head while preserving the shown list order.