updating DIRECTORY.md

Author: github-actions

DIRECTORY.md

@@ -149,6 +149,7 @@
 ## Recursive
   * [BinarySearch](https://github.com/TheAlgorithms/Javascript/blob/master/Recursive/BinarySearch.js)
   * [EucledianGCD](https://github.com/TheAlgorithms/Javascript/blob/master/Recursive/EucledianGCD.js)
+  * [factorial](https://github.com/TheAlgorithms/Javascript/blob/master/Recursive/factorial.js)
   * [FibonacciNumberRecursive](https://github.com/TheAlgorithms/Javascript/blob/master/Recursive/FibonacciNumberRecursive.js)
   * [Palindrome](https://github.com/TheAlgorithms/Javascript/blob/master/Recursive/Palindrome.js)
   * [TowerOfHanoi](https://github.com/TheAlgorithms/Javascript/blob/master/Recursive/TowerOfHanoi.js)