Snippet format update

To match the starter (for the migration)

snippets/pullAtIndex.md

@@ -1,4 +1,7 @@
-### pullAtIndex
+---
+title: pullAtIndex
+tags: array,advanced
+---
 
 Mutates the original array to filter out the values at the specified indexes.
 
@@ -21,4 +24,4 @@ const pullAtIndex = (arr, pullArr) => {
 ```js
 let myArray = ['a', 'b', 'c', 'd'];
 let pulled = pullAtIndex(myArray, [1, 3]); // myArray = [ 'a', 'c' ] , pulled = [ 'b', 'd' ]
-```
+```