Snippet format update

To match the starter (for the migration)

snippets/unary.md

@@ -1,4 +1,7 @@
-### unary
+---
+title: unary
+tags: adapter,function,intermediate
+---
 
 Creates a function that accepts up to one argument, ignoring any additional arguments.
 
@@ -10,4 +13,4 @@ const unary = fn => val => fn(val);
 
 ```js
 ['6', '8', '10'].map(unary(parseInt)); // [6, 8, 10]
-```
+```