added unit test

Author: Adithya

src/algorithms/sorting/radix-sort.js

@@ -16,4 +16,6 @@ function radixSort(arr) {
        divisor *= 10;
     }
     return arr;
- }
+ }
+//  unit test
+console.log(radixSort([5,3,88,235,65,23,4632,234]))