default File getSnapshotRoot() {
    return null;
  }
Since Ratis 2.4.1, RatisConsensus allows statemachine to customize its own snapshot storage.
Currently only DataRegionStateMachine will use this interface.

@return statemachine snapshot root
iotdb-core/consensus/src/main/java/org/apache/iotdb/consensus/IStateMachine.java