add addKeyValueAnnotationsAsText flag in AutoML

[LittleLittleCloud]

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dotnet/machinelearning-modelbuilder#2418

[codecov]

Codecov Report

Merging #6535 (9915e47) into main (bc250df) will decrease coverage by 0.00%.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6535      +/-   ##
==========================================
- Coverage   68.46%   68.45%   -0.01%     
==========================================
  Files        1173     1173              
  Lines      247651   247651              
  Branches    25846    25846              
==========================================
- Hits       169543   169537       -6     
- Misses      71378    71383       +5     
- Partials     6730     6731       +1     

Flag	Coverage Δ
Debug	68.45% <ø> (-0.01%)	⬇️
production	62.84% <ø> (-0.01%)	⬇️
test	88.92% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
src/Microsoft.ML.FastTree/Training/StepSearch.cs	57.42% <0.00%> (-4.96%)	⬇️
src/Microsoft.ML.LightGbm/LightGbmTrainerBase.cs	79.50% <0.00%> (-0.28%)	⬇️
...ML.Transforms/Text/StopWordsRemovingTransformer.cs	86.53% <0.00%> (+0.14%)	⬆️