Skip sdk_validation_test again (#42091)

diff --git a/packages/flutter_tools/test/general.shard/dart/sdk_validation_test.dart b/packages/flutter_tools/test/general.shard/dart/sdk_validation_test.dart
index 7259b13..e1dc2a6 100644
--- a/packages/flutter_tools/test/general.shard/dart/sdk_validation_test.dart
+++ b/packages/flutter_tools/test/general.shard/dart/sdk_validation_test.dart
@@ -56,7 +56,7 @@
       tryToDelete(projectDirectory);
       Cache.enableLocking();
     }
-  });
+  }, skip: true);
 }
 
 Future<int> analyze(AnalysisServer server) async {