Fix coroutines yielding the same value twice

Upsilon/Evaluator/Script.cs

@@ -122,7 +122,10 @@ namespace Upsilon.Evaluator
             {
                 var current = coroutine.Current;
                 if (current is ScriptType scriptType)
+                {
                     yield return scriptType.ToCSharpObject();
+                    continue;
+                }
                 yield return current;
             }
         }