fix(traits5): make exercise prefer trait-based solution

closes #1088

exercises/traits/traits5.rs

@@ -18,16 +18,20 @@ pub trait OtherTrait {
     }
 }
 
-struct SomeStruct {
-    name: String,
-}
+struct SomeStruct {}
+struct OtherStruct {}
 
 impl SomeTrait for SomeStruct {}
 impl OtherTrait for SomeStruct {}
+impl SomeTrait for OtherStruct {}
+impl OtherTrait for OtherStruct {}
 
 // YOU MAY ONLY CHANGE THE NEXT LINE
 fn some_func(item: ??) -> bool {
     item.some_function() && item.other_function()
 }
 
-fn main() {}
+fn main() {
+    some_func(SomeStruct {});
+    some_func(OtherStruct {});
+}