[fix](fe) LIST partition table support modify default bucket num

[htyoung]

Proposed changes

bp #39696

Issue Number: close#39684

CREATETABLE `test1` (
`id1`VARCHAR(255) NULL COMMENT 'id1',
`id2`VARCHAR(255) NULL COMMENT 'id2',
`event_time`VARCHAR(255) NULL COMMENT '事件时间',
`event_date`VARCHAR(255) NULL COMMENT '事件日期',
`event_ts`VARCHAR(256) NULL COMMENT '事件发生时间戳(毫秒)',
`dt`VARCHAR(255) NOT NULL COMMENT '日期分区',
`hr`VARCHAR(255) NOT NULL COMMENT '小时分区'
) ENGINE = OLAP DUPLICATE KEY(`id1`) COMMENT 'xxx' PARTITION BY LIST(`dt`, `hr`) (
PARTITION p2024082021 VALUESIN (("2024-08-20", "21"))
) DISTRIBUTED BY HASH(`dt`, `hr`) BUCKETS 2 PROPERTIES (
"replication_allocation"="tag.location.default: 1",
"min_load_replica_num"="-1",
"is_being_synced"="false",
"storage_medium"="hdd",
"storage_format"="V2",
"inverted_index_storage_format"="V1",
"light_schema_change"="true",
"disable_auto_compaction"="false",
"enable_single_replica_compaction"="false",
"group_commit_interval_ms"="10000",
"group_commit_data_bytes"="134217728"
);

1. 修改前表已有分区的bucket num为2
   

2. 修改List分区表bucket num（从2 -> 4）
   

3. 修改List分区后，添加的新分区bucket num为4
   

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[morningman]

LGTM, please add unit test

[morningman]

LGTM

[morningman]

run buildall

[github-actions]

PR approved by at least one committer and no changes requested.

[github-actions]

PR approved by anyone and no changes requested.

[dataroaring]

Please insert values to table and alter bucket and check values.

[dataroaring]

Why is the pr not go to master?

[htyoung]

Why is the pr not go to master?

master branch has another same pr #39696

[htyoung]

Please insert values to table and alter bucket and check values.

I have updated the regression-test suit

[morningman]

run buildall