Snippet format update

To match the starter (for the migration)

snippets/sample.md

@@ -1,4 +1,7 @@
-### sample
+---
+title: sample
+tags: array,random,beginner
+---
 
 Returns a random element from an array.
 
@@ -11,4 +14,4 @@ const sample = arr => arr[Math.floor(Math.random() * arr.length)];
 
 ```js
 sample([3, 7, 9, 11]); // 9
-```
+```