[I] create view with multi union use the first union schema as the final view schema [datafusion]

[via GitHub]

Curricane opened a new issue, #14132:
URL: https://github.com/apache/datafusion/issues/14132

   ### Describe the bug
   
   create view with multi union use the first union schema as the final view 
schema. eg:
   use the latest datafusion-cli
   ```sql
   CREATE UNBOUNDED EXTERNAL TABLE test1 (
       id  INT NOT NULL,
       id1  INT NOT NULL,
   )
   STORED AS CSV
   LOCATION '/home/cc/demo1.csv';
   
   CREATE UNBOUNDED EXTERNAL TABLE test2 (
       id  INT NOT NULL,
       id1  INT,
   )
   STORED AS CSV
   LOCATION '/home/cc/demo2.csv';
   
   CREATE VIEW adv_001
   AS 
   SELECT id, id1 from test1
   UNION ALL
   SELECT id, id1 from test2;
   
   CREATE VIEW adv_002
   AS 
   SELECT id, id1 from test2
   UNION ALL
   SELECT id, id1 from test1;
   ```
   when describe adv_001 and adv_002，get different result
   ```log
   > describe adv_001;
   +-------------+-----------+-------------+
   | column_name | data_type | is_nullable |
   +-------------+-----------+-------------+
   | id          | Int32     | NO          |
   | id1         | Int32     | NO          |
   +-------------+-----------+-------------+
   2 row(s) fetched.
   Elapsed 0.002 seconds.
   
   > describe adv_002;
   +-------------+-----------+-------------+
   | column_name | data_type | is_nullable |
   +-------------+-----------+-------------+
   | id          | Int32     | NO          |
   | id1         | Int32     | YES         |
   +-------------+-----------+-------------+
   2 row(s) fetched.
   Elapsed 0.002 seconds
   ```
   
   In other words, if there are multiple UNION when creating a view, the schema 
of multiple UNIONs will not be processed, such as TypeCoercion
   
   ### To Reproduce
   
   see describe
   
   ### Expected behavior
   
   if there are multiple UNION when creating a view, the schema of multiple 
UNIONs should  be processed, such as TypeCoercion
   
   ### Additional context
   
   I will fix it.


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