Update README.md

Author: trekhleb

README.md

@@ -15,7 +15,6 @@
 8. [Tree](https://github.com/trekhleb/javascript-algorithms/tree/master/src/data-structures/tree)
     * [Binary Search Tree](https://github.com/trekhleb/javascript-algorithms/tree/master/src/data-structures/tree/binary-search-tree)
     * [AVL Tree](https://github.com/trekhleb/javascript-algorithms/tree/master/src/data-structures/tree/avl-tree)
-    * 2-3 Tree
     * Red-Black Tree
     * Suffix Tree
     * Segment Tree or Interval Tree