Add IterationDataAttribute

[sharwell]

No description provided.

[sharwell]

We should consider consolidating the namespaces Microsoft.ML.TestFramework and Microsoft.ML.TestFrameworkCommon, but I left that for another change.

[codecov]

Codecov Report

Merging #4561 into master will increase coverage by <.01%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master    #4561      +/-   ##
==========================================
+ Coverage   75.12%   75.13%   +<.01%     
==========================================
  Files         908      909       +1     
  Lines      160229   160240      +11     
  Branches    17250    17252       +2     
==========================================
+ Hits       120372   120392      +20     
+ Misses      35041    35025      -16     
- Partials     4816     4823       +7

Flag	Coverage Δ
#Debug	75.13% <0%> (ø)	⬆️
#production	70.53% <ø> (+0.01%)	⬆️
#test	90.28% <0%> (-0.04%)	⬇️

Impacted Files	Coverage Δ
...ameworkCommon/Attributes/IterationDataAttribute.cs	0% <0%> (ø)
...rosoft.ML.AutoML/ColumnInference/TextFileSample.cs	59.6% <0%> (-2.65%)	⬇️
...L.AutoML/TrainerExtensions/TrainerExtensionUtil.cs	85.15% <0%> (-1.75%)	⬇️
...soft.ML.Data/DataLoadSave/Text/TextLoaderCursor.cs	84.7% <0%> (-0.61%)	⬇️
...soft.ML.TestFramework/DataPipe/TestDataPipeBase.cs	76.08% <0%> (-0.4%)	⬇️
...ML.Transforms/Text/StopWordsRemovingTransformer.cs	86.1% <0%> (-0.16%)	⬇️
....ML.AutoML/PipelineSuggesters/PipelineSuggester.cs	84.03% <0%> (+0.84%)	⬆️
...soft.ML.Transforms/Text/WordEmbeddingsExtractor.cs	87.52% <0%> (+1.13%)	⬆️
...icrosoft.ML.AutoML/Experiment/SuggestedPipeline.cs	92.78% <0%> (+4.12%)	⬆️
... and 2 more