Snippet format update

To match the starter (for the migration)

snippets/mapObject.md

@@ -1,4 +1,7 @@
-### mapObject
+---
+title: mapObject
+tags: array,object,advanced
+---
 
 Maps the values of an array to an object using a function, where the key-value pairs consist of the stringified value as the key and the mapped value.
 
@@ -14,4 +17,4 @@ const mapObject = (arr, fn) =>
 ```js
 const squareIt = arr => mapObject(arr, a => a * a);
 squareIt([1, 2, 3]); // { 1: 1, 2: 4, 3: 9 }
-```
+```