protected CommonPartitionEvaluator evaluator() {
    if (evaluator == null) {
      evaluator = buildEvaluator();
    }
    return evaluator;
  }
Reserved Delete files are Delete files which are related to Data files not optimized in this
plan.
amoro-format-iceberg/src/main/java/org/apache/amoro/optimizing/plan/AbstractPartitionPlan.java