ci: enable GHA windows-cmake testing

[scotthart]

Enable GHA windows+cmake testing with a reduced build matrix until kokoro build is working.

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This change is 

[gemini-code-assist]

Note

Gemini is unable to generate a summary for this pull request due to the file types involved not being currently supported.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.63%. Comparing base (d83c3a9) to head (54cc0ed).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #15983   +/-   ##
=======================================
  Coverage   92.63%   92.63%           
=======================================
  Files        2334     2334           
  Lines      214633   214633           
=======================================
+ Hits       198826   198832    +6     
+ Misses      15807    15801    -6     

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