Use correct async helpers and awaits in LanguageFeatures/Parts-with-imports/scope_A06_t03.dart (#3384)

Co-authored-by: Nate Biggs <natebiggs@google.com>
diff --git a/LanguageFeatures/Parts-with-imports/scope_A06_t03.dart b/LanguageFeatures/Parts-with-imports/scope_A06_t03.dart
index d4996b7..6b89017 100644
--- a/LanguageFeatures/Parts-with-imports/scope_A06_t03.dart
+++ b/LanguageFeatures/Parts-with-imports/scope_A06_t03.dart
@@ -28,6 +28,8 @@
 import '../../Utils/expect.dart';
 part 'scope_A06_t03_part1.dart';
 
-main() {
-  testPart2();
+Future<void> main() async {
+  asyncStart();
+  await testPart2();
+  asyncEnd();
 }