message: Avoid executing failed pending query result
diff: @@ -1074,6 +1074,9 @@ unique_ptr<QueryResult> ClientContext::Execute(const shared_ptr<Relation> &relat
  auto lock = LockContext();
  auto &expected_columns = relation->Columns();
  auto pending = PendingQueryInternal(*lock, relation, false);
  + if (!pending->success) {
  + return make_unique<MaterializedQueryResult>(pending->GetErrorObject());
  + }
  unique_ptr<QueryResult> result;
  result = ExecutePendingQueryInternal(*lock, *pending);
  