private void checkOldProcWalDir(File newDir) {
    File oldDir = new File(CommonDescriptor.getInstance().getConfig().getOldProcedureWalFolder());
    if (oldDir.exists()) {
      FileUtils.moveFileSafe(oldDir, newDir);
    }
  }
clean all the wal, used for unit test.
iotdb-core/confignode/src/main/java/org/apache/iotdb/confignode/procedure/store/ConfigProcedureStore.java