Update countOccurrences function

Removes unnecessary addition of `0`.

snippets/countOccurrences.md

@@ -5,7 +5,7 @@ Counts the occurrences of a value in an array.
 Use `Array.reduce()` to increment a counter each time you encounter the specific value inside the array.
 
 ```js
-const countOccurrences = (arr, val) => arr.reduce((a, v) => (v === val ? a + 1 : a + 0), 0);
+const countOccurrences = (arr, val) => arr.reduce((a, v) => (v === val ? a + 1 : a), 0);
 ```
 
 ```js