Adapt PolyBenchLauncher to GraalWasm API changes.

Author: woess

vm/src/org.graalvm.polybench/src/org/graalvm/polybench/PolyBenchLauncher.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2020, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2020, 2025, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -591,7 +591,7 @@ public void run() {
         // language-specific lookup
         switch (languageId) {
             case "wasm":
-                result = evalSourceValue.getMember(memberName);
+                result = evalSourceValue.newInstance().getMember("exports").getMember(memberName);
                 break;
             case "java":
                 // Espresso doesn't provide methods as executable values.