fix: Properly fetch type of full None List Series

[coastalwhite]

Fixes #18910, #18911.

[coastalwhite]

Windows CI issue again

[codecov]

Codecov Report

Attention: Patch coverage is 90.94077% with 26 lines in your changes missing coverage. Please review.

Project coverage is 79.88%. Comparing base (2467b27) to head (9d065aa).
Report is 9 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-core/src/frame/column/scalar.rs	92.04%	14 Missing ⚠️
crates/polars-core/src/series/any_value.rs	83.01%	9 Missing ⚠️
crates/polars-ops/src/series/ops/duration.rs	75.00%	2 Missing ⚠️
crates/polars-io/src/utils/other.rs	66.66%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff            @@
##             main   #18916    +/-   ##
========================================
  Coverage   79.88%   79.88%            
========================================
  Files        1521     1523     +2     
  Lines      206850   206990   +140     
  Branches     2906     2906            
========================================
+ Hits       165243   165363   +120     
- Misses      41059    41079    +20     
  Partials      548      548            

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