fix(query): support subquery in pivot

[Dragonliu2018]

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Summary

• fixes: bug: pivot query can not support subquery #16556

Pivot supports subquery now. For example, the following three types of queries:

1. from + subquery:

SELECT *
FROM (select * from monthly_sales)
PIVOT(SUM(amount) FOR MONTH IN ('JAN', 'FEB', 'MAR', 'APR'))
ORDER BY EMPID;

2. in + subquery:

SELECT * 
FROM monthly_sales
PIVOT(SUM(amount) FOR MONTH IN (select distinct month from monthly_sales))
ORDER BY EMPID;

3. combination:

  SELECT * 
  FROM (select * from monthly_sales)
  PIVOT(SUM(amount) FOR MONTH IN (select distinct month from monthly_sales))
  ORDER BY EMPID;

Reproduce document: https://docs.databend.com/sql/sql-commands/query-syntax/query-pivot

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Unpivot currently only supports the from + subquery type of subquery, consistent with Snowflake's behavior.

SELECT * FROM (SELECT * FROM monthly_sales_1)
UNPIVOT(sales FOR month IN (jan, feb, mar, april))
ORDER BY empid;

Snowflakes reference document: https://docs.snowflake.com/en/sql-reference/constructs/unpivot
Reproduce document: https://docs.databend.com/sql/sql-commands/query-syntax/query-unpivot

Tests

• Unit Test
• Logic Test
• Benchmark Test
• No Test - Explain why

Type of change

• Bug Fix (non-breaking change which fixes an issue)
• New Feature (non-breaking change which adds functionality)
• Breaking Change (fix or feature that could cause existing functionality not to work as expected)
• Documentation Update
• Refactoring
• Performance Improvement
• Other (please describe):

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This change is