fix(iceberg): fix iceberg time travel timezone

[chenzl25]

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What's changed and what's your intention?

• Resolve fix: iceberg time travel timestamp should respect session timezone #20036

Example

set timezone = 'asia/shanghai';
select * from t for system_time as of '2025-01-09 15:12:50.669';

Checklist

• I have written necessary rustdoc comments.
• I have added necessary unit tests and integration tests.
• I have added test labels as necessary.
• I have added fuzzing tests or opened an issue to track them.
• My PR contains breaking changes.
• My PR changes performance-critical code, so I will run (micro) benchmarks and present the results.
• My PR contains critical fixes that are necessary to be merged into the latest release.

Documentation

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Release note