Fix for conditional error in root cause analysis additions

[klausmh]

Fix for error in refactoring RCA code. This establishes the same logic in the OrderDimensions code as in the previous version, cf.

machinelearning/src/Microsoft.ML.TimeSeries/RootCauseAnalyzer.cs

Line 460 in 1c2469f

private BestDimension FindBestDimension(SortedDictionary<BestDimension, double> valueMap, Dictionary<BestDimension, double> valueRatioMap, double meanGain, bool isLeavesLevel = true)

[harishsk]

[codecov]

Codecov Report

Merging #5269 into master will increase coverage by 0.07%.
The diff coverage is 50.00%.

@@            Coverage Diff             @@
##           master    #5269      +/-   ##
==========================================
+ Coverage   73.62%   73.69%   +0.07%     
==========================================
  Files        1022     1022              
  Lines      190057   190056       -1     
  Branches    20445    20444       -1     
==========================================
+ Hits       139931   140071     +140     
+ Misses      44598    44474     -124     
+ Partials     5528     5511      -17     

Flag	Coverage Δ
#Debug	73.69% <50.00%> (+0.07%)	⬆️
#production	69.46% <50.00%> (+0.09%)	⬆️
#test	87.61% <ø> (ø)

Impacted Files	Coverage Δ
src/Microsoft.ML.TimeSeries/RootCauseAnalyzer.cs	54.62% <50.00%> (-0.08%)	⬇️
...icrosoft.ML.AutoML/Experiment/SuggestedPipeline.cs	88.65% <0.00%> (-4.13%)	⬇️
src/Microsoft.ML.Maml/MAML.cs	23.78% <0.00%> (-0.98%)	⬇️
...StandardTrainers/Standard/LinearModelParameters.cs	66.32% <0.00%> (-0.26%)	⬇️
src/Microsoft.ML.Data/Utils/LossFunctions.cs	67.35% <0.00%> (+0.51%)	⬆️
src/Microsoft.ML.AutoML/Sweepers/Parameters.cs	85.16% <0.00%> (+0.84%)	⬆️
...oft.ML.StandardTrainers/Standard/SdcaMulticlass.cs	92.49% <0.00%> (+1.02%)	⬆️
...crosoft.ML.StandardTrainers/Optimizer/Optimizer.cs	73.12% <0.00%> (+1.15%)	⬆️
....ML.AutoML/PipelineSuggesters/PipelineSuggester.cs	86.55% <0.00%> (+2.52%)	⬆️
...crosoft.ML.StandardTrainers/Standard/SdcaBinary.cs	88.48% <0.00%> (+3.24%)	⬆️
... and 3 more