message: Fix integration test open_pool_ledger_works_for_twice.
diff: @@ -39,10 +39,11 @@ fn create_pool_ledger_config_works() {
  #[test]
  fn open_pool_ledger_works() {
  - let res = PoolUtils::create_pool_ledger_config("pool1");
  + let name = "pool_open";
  + let res = PoolUtils::create_pool_ledger_config(name);
  assert!(res.is_ok());
  - let res = PoolUtils::open_pool_ledger("pool1");
  + let res = PoolUtils::open_pool_ledger(name);
  assert!(res.is_ok());
  TestUtils::cleanup_storage();
  @@ -51,11 +52,14 @@ fn open_pool_ledger_works() {
  #[test]
  fn open_pool_ledger_works_for_twice() {
  TestUtils::cleanup_storage();
  + let pool_name = "pool_open_twice";
  - let res = PoolUtils::create_pool_ledger_config("pool1");
  + let res = PoolUtils::create_pool_ledger_config(pool_name);
  assert!(res.is_ok());
  - let res = PoolUtils::open_pool_ledger("pool1");
  + let res = PoolUtils::open_pool_ledger(pool_name);
  + assert!(res.is_ok());
  + let res = PoolUtils::open_pool_ledger(pool_name);
  assert_match!(Err(ErrorCode::PoolLedgerInvalidPoolHandle), res);
  TestUtils::cleanup_storage();
  