[BUG] Fix parquet timestamp tz roundtrip inference

[jaychia]

This required a fix in our arrow2 fork: Eventual-Inc/arrow2@3a23c78

Essentially when Parquet has a type that is "timezone aware", Arrow2 will always infer it as "+00:00" (not None as previously assumed). However if the embedded Arrow schema on the Parquet file tells us that the timezone should actually be something else, we need to override "+00:00" with the one provided by the embedded Arrow schema.

[codecov]

Codecov Report

Merging #1625 (4fd301b) into main (427a4fe) will not change coverage.
Report is 4 commits behind head on main.
The diff coverage is n/a.

Additional details and impacted files

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  Misses        639      639