chore: use raw sql as task SQL instead of pretty one

[ZhiHanZ]

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Summary

Briefly describe what this PR aims to solve. Include background context that will help reviewers understand the purpose of the PR.

Use raw formatted SQL instead of prettied one.
Previous, task SQL used the pretty_statement function and generate prettified SQL for further cloud service execution, but it seems like there are some SQL may parse in different way and unable to execute anymore. for example

copy into @stream_stage from (
        SELECT
            CASE
                WHEN (RAND() * 10)::INT % 4 = 0 THEN 'a'
                WHEN (RAND() * 10)::INT % 4 = 1 THEN 'b'
                WHEN (RAND() * 10)::INT % 4 = 2 THEN 'c'
                ELSE 'd'
            END AS level
        FROM numbers(500000)
    ) FILE_FORMAT = (
        TYPE = PARQUET
    );

its pretty formatted string is

COPY INTO Stage("stream_stage")
FROM (
    SELECT CASE
        WHEN (((RAND() * 10)::Int32 % 4) = 0) THEN 'a',
        WHEN (((RAND() * 10)::Int32 % 4) = 1) THEN 'b',
        WHEN (((RAND() * 10)::Int32 % 4) = 2) THEN 'c',
        ELSE 'd'
    END AS level
    FROM numbers(500000)
)
FILE_FORMAT = (
    type = "PARQUET"
)
SINGLE = false;

which is unable to execute

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 

[ZhiHanZ]

github down, ci cannot work...