fix(rust): Ensure ListPrimitiveBuilder dtype invariant is asserted

[ritchie46]

@coastalwhite FYI

[codecov]

Codecov Report

Attention: Patch coverage is 80.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 79.88%. Comparing base (d3f8a5c) to head (f3a89a7).
Report is 49 commits behind head on main.

Files with missing lines	Patch %	Lines
...s-core/src/chunked_array/builder/list/primitive.rs	80.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #18889      +/-   ##
==========================================
- Coverage   79.89%   79.88%   -0.02%     
==========================================
  Files        1520     1520              
  Lines      206552   206555       +3     
  Branches     2906     2906              
==========================================
- Hits       165020   164997      -23     
- Misses      40984    41010      +26     
  Partials      548      548              

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