updating DIRECTORY.md

Author: github-actions

DIRECTORY.md

@@ -102,6 +102,7 @@
  * [GridGet](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/GridGet.js)
  * [isDivisible](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/isDivisible.js)
  * [isOdd](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/isOdd.js)
+ * [MatrixMultiplication](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/MatrixMultiplication.js)
  * [MeanSquareError](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/MeanSquareError.js)
  * [ModularBinaryExponentiationRecursive](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/ModularBinaryExponentiationRecursive.js)
  * [NumberOfDigits](https://github.com/TheAlgorithms/Javascript/blob/master/Maths/NumberOfDigits.js)