perf(python): Use PyO3 to convert between Python and Rust datetimes

[bschoenmaeckers]

fixes #16199

Waiting for pyo3 v0.23.4 to be released. PyO3/pyo3#4835

[codecov]

Codecov Report

Attention: Patch coverage is 89.36170% with 5 lines in your changes missing coverage. Please review.

Project coverage is 79.02%. Comparing base (a0d96f2) to head (0a3fa09).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-python/src/conversion/datetime.rs	72.22%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #20660      +/-   ##
==========================================
- Coverage   79.03%   79.02%   -0.01%     
==========================================
  Files        1559     1559              
  Lines      221238   221235       -3     
  Branches     2529     2529              
==========================================
- Hits       174851   174834      -17     
- Misses      45806    45819      +13     
- Partials      581      582       +1     

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[bschoenmaeckers]

Should this return the timezone info instead of None in the cases where there is one?

[ritchie46]

Currently we don't. I think eventually we have to, but then we also need to infer which timezone to set on the dtype.

[codspeed-hq]

CodSpeed Performance Report

Merging #20660 will not alter performance

_{Comparing bschoenmaeckers:datetime-convert (0a3fa09) with main (a0d96f2)}

Summary

✅ 41 untouched benchmarks

[ritchie46]

Thank you @bschoenmaeckers!