Add variable declaration (#34702)

* Declare variable

* Update guide/english/certifications/javascript-algorithms-and-data-structures/functional-programming/use-the-map-method-to-extract-data-from-an-array/index.md

Co-Authored-By: ojeytonwilliams <ojeytonwilliams@gmail.com>

guide/english/certifications/javascript-algorithms-and-data-structures/functional-programming/use-the-map-method-to-extract-data-from-an-array/index.md

@@ -14,7 +14,7 @@ array.prototype.map takes a function as in input and returns an array. The retur
 
 ## ![:rotating_light:](https://forum.freecodecamp.com/images/emoji/emoji_one/rotating_light.png?v=3 ":rotating_light:") Intermediate Code Solution:
 ```javascript
-  rating = watchList.map( (item) => ({"title":item["Title"], "rating":item["imdbRating"]}) );
+  const rating = watchList.map(item => ({title: item["Title"], rating: item["imdbRating"]}));
 ```
  ### Code Explanation:
 Using ES6 notation, each item in array is processed to extract title and rating.