public List<TSeriesPartitionSlot> filterUnassignedSchemaPartitionSlots(
      List<TSeriesPartitionSlot> partitionSlots) {
    List<TSeriesPartitionSlot> result = new Vector<>();

    partitionSlots.forEach(
        seriesPartitionSlot -> {
          if (!schemaPartitionMap.containsKey(seriesPartitionSlot)) {
            result.add(seriesPartitionSlot);
          }
        });

    return result;
  }
Only Leader use this interface. Filter unassigned SchemaPartitionSlots within the specific
StorageGroup.

@param partitionSlots List<TSeriesPartitionSlot>
@return Unassigned PartitionSlots
iotdb-core/node-commons/src/main/java/org/apache/iotdb/commons/partition/SchemaPartitionTable.java