fix(parquet): handle nested data types correctly

[wcy-fdu]

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What's changed and what's your intention?

Here, there was a bug previously where the columns in the parquet file metadata returned the flattened columns, while parquet_to_arrow_schema.fields returned the un flattened schema. Therefore, when the parquet file contains nested columns, such as Structs, their lengths differ, which can lead to an index out of bound panic.

This PR fixes the issue by not performing column trimming for parquet files that contain nested columns, and replaces the previous method of finding data types by index with a method that find them up by name.

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

• My PR needs documentation updates.

Release note

[wcy-fdu]

@hzxa21 @chenzl25 PTAL❤️
Users are waiting for this fix.

[hzxa21]

Generally LGTM. @chenzl25 PTAL

[gru-agent]

This pull request has been modified. If you want me to regenerate unit test for any of the files related, please find the file in "Files Changed" tab and add a comment @gru-agent. (The github "Comment on this file" feature is in the upper right corner of each file in "Files Changed" tab.)

[chenzl25]

LGTM