Also update resolve to method

Author: rmosolgo

guides/fields/limits.md

@@ -16,9 +16,10 @@ Always limit the number of items which can be returned from a list field. For ex
 field :items, Types::ItemType do
   # Cap the number of items at 30
   argument :limit, Integer, default_value: 20, prepare: ->(limit, ctx) {[limit, 30].min}
-  resolve ->(obj, args, ctx) {
-    obj.items.limit(args[:limit])
-  }
+end
+
+def items(limit:)
+  object.items.limit(limit)
 end
 ```