@Override
  public String name() {
    return "MigrateToMixedFormatTable";
  }
migrate a v1 table to mixed-format table. will reuse file in v1 table , but delete metadata in
session catalog
amoro-format-mixed/amoro-mixed-spark/v3.2/amoro-mixed-spark-3.2/src/main/java/org/apache/amoro/spark/command/MigrateToMixedFormatCommand.java