fix: use polars.__version__ in version check

[lukemanley]

Summary

Polars has a few different installations options including:

• pip install polars
• pip install polars-u64-idx
• pip install polars-lts-cpu

The last one was not covered by the existing version check. This PR changes the version check to use polars.__version__ which should work for all installation types.

Related GitHub Issues and PRs

• Ref: #

Checklist

• I understand and agree to the Code of Conduct.
• I have followed the Style Guide for Python Code as best as possible for the submitted code.
• I have added pytest unit tests for any new functionality.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.91%. Comparing base (5913c57) to head (f167bd0).
Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #505      +/-   ##
==========================================
+ Coverage   88.88%   88.91%   +0.02%     
==========================================
  Files          44       44              
  Lines        5216     5212       -4     
==========================================
- Hits         4636     4634       -2     
+ Misses        580      578       -2     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[machow]

afaict this is the right approach in this situation since in polars, many distribution names may correspond with the module polars. (and version() uses distribution name)