Gardening: improve debug output in standalone/io/socket_ipv6_test.dart.

tests/standalone/io/socket_ipv6_test.dart

Index: tests/standalone/io/socket_ipv6_test.dart
diff --git a/tests/standalone/io/socket_ipv6_test.dart b/tests/standalone/io/socket_ipv6_test.dart
index 6b919579c6681ce2fd23c7f731cede218a6c903f..8eaa6626c8e5c0284a849c0a6654947a02a54464 100644
--- a/tests/standalone/io/socket_ipv6_test.dart
+++ b/tests/standalone/io/socket_ipv6_test.dart
@@ -129,13 +129,13 @@ Future testIPv4toIPv6_IPV6Only() {
   });
 }
 
-void main() {
-  testIPv6toIPv6();                /// 01: ok
-  testIPv4toIPv6();                /// 02: ok
-  testIPv4toIPv4();                /// 03: ok
-  testIPv6Lookup();                /// 04: ok
-  testIPv4Lookup();                /// 05: ok
+main() async {
+  await testIPv6toIPv6();                /// 01: ok
+  await testIPv4toIPv6();                /// 02: ok
+  await testIPv4toIPv4();                /// 03: ok
+  await testIPv6Lookup();                /// 04: ok
+  await testIPv4Lookup();                /// 05: ok
 
-  retry(testIPv6toIPv4);           /// 06: ok
-  retry(testIPv4toIPv6_IPV6Only);  /// 07: ok
+  await retry(testIPv6toIPv4);           /// 06: ok
+  await retry(testIPv4toIPv6_IPV6Only);  /// 07: ok
 }