chore(main): release 1.38.0

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🤖 I have created a release beep boop

1.38.0 (2025-02-24)

Features

• (Preview) Support diff aggregation for timestamp series. (#1405) (abe48d6)
• Add GeoSeries.from_wkt() and GeoSeries.to_wkt() (#1401) (2993b28)
• Support DF.array(copy=True) (#1403) (693ed8c)
• Support routines with ARRAY return type in read_gbq_function (#1412) (4b60049)

Bug Fixes

• Calling to_timdelta() over timedeltas no longer changes their values (#1411) (650a190)
• Replace empty dict with None to avoid mutable default arguments (#1416) (fa4e3ad)

Performance Improvements

• Avoid redundant SQL casts (#1399) (6ee48d5)

Dependencies

• Remove scikit-learn and sqlalchemy as required dependencies (#1296) (fd8bc89)

Documentation

• Add samples using SQL methods via the bigframes.bigquery module (#1358) (f54e768)
• Add snippets for visualizing a time series and creating a time series model for the Limit forecasted values in time series model tutorial (#1310) (c6c9120)

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🤖 Created releases:

• v1.38.0

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