public MergeResult whenMatched(
        BiFunction<Record, Record, Boolean> condition, BiFunction<Record, Record, Record> action) {
      this.matchActions.add(Pair.of(condition, action));
      return this;
    }
if condition(target, source) test for true. then apply action(target, source) to target
records.

@param condition - condition(target, source): bool
@param action -> action(target, source): Record if return null, target will be deleted.
@return this.
amoro-format-mixed/amoro-mixed-spark/amoro-mixed-spark-3-common/src/test/java/org/apache/amoro/spark/test/utils/ExpectResultUtil.java