### What problem does this PR solve?
Problem Summary:
When fall back to old planner, the partition pruning of external table
will fail,
and NPE will be throw like:
```
2025-04-14 16:22:33,427 WARN (mysql-nio-pool-19697|237161) [HiveScanNode.getSplits():189] get file split failed for table: dwd_log_fact_channel_track_result_hi
java.lang.NullPointerException: null
at org.apache.doris.datasource.hive.source.HiveScanNode.getPartitions(HiveScanNode.java:137) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.datasource.hive.source.HiveScanNode.getSplits(HiveScanNode.java:171) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.datasource.FileQueryScanNode.createScanRangeLocations(FileQueryScanNode.java:366) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.datasource.FileQueryScanNode.doFinalize(FileQueryScanNode.java:222) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.datasource.FileQueryScanNode.finalize(FileQueryScanNode.java:208) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.PlanNode.finalize(PlanNode.java:722) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.JoinNodeBase.finalize(JoinNodeBase.java:456) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.PlanNode.finalize(PlanNode.java:722) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.JoinNodeBase.finalize(JoinNodeBase.java:456) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.PlanNode.finalize(PlanNode.java:722) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.AggregationNode.finalize(AggregationNode.java:402) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.PlanNode.finalize(PlanNode.java:722) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.SetOperationNode.finalize(SetOperationNode.java:158) ~[doris-fe.jar:1.2-SNAPSHOT]
at org.apache.doris.planner.PlanNode.finalize(PlanNode.java:722) ~[doris-fe.jar:1.2-SNAPSHOT]
```
This error msg is very confusing. So this PR return a more explicit
error msg.
### Release note
None
# Licensed to the Apache Software Foundation (ASF) under one # or more contributor license agreements. See the NOTICE file # distributed with this work for additional information # regarding copyright ownership. The ASF licenses this file # to you under the Apache License, Version 2.0 (the # "License"); you may not use this file except in compliance # with the License. You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, # software distributed under the License is distributed on an # "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY # KIND, either express or implied. See the License for the # specific language governing permissions and limitations # under the License. # fe-common This module is used to store some common classes of other modules. # spark-dpp This module is Spark DPP program, used for Spark Load function. Depends: fe-common # fe-core This module is the main process module of FE. Depends: fe-common, spark-dpp