Fix documentation of SvmLightLoader

[yaeldekel]

Together with PR #4614, fixes #4610 .

[codecov]

Codecov Report

Merging #4616 into master will increase coverage by 0.76%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #4616      +/-   ##
==========================================
+ Coverage   74.88%   75.64%   +0.76%     
==========================================
  Files         935      938       +3     
  Lines      168440   168623     +183     
  Branches    18189    18206      +17     
==========================================
+ Hits       126132   127557    +1425     
+ Misses      37325    36029    -1296     
- Partials     4983     5037      +54

Flag	Coverage Δ
#Debug	75.64% <ø> (+0.76%)	⬆️
#production	71.27% <ø> (+0.99%)	⬆️
#test	90.43% <ø> (ø)	⬆️

Impacted Files	Coverage Δ
....Transforms/SvmLight/SvmLightLoaderSaverCatalog.cs	100% <ø> (ø)	⬆️
...Microsoft.ML.Transforms/SvmLight/SvmLightLoader.cs	95.75% <ø> (ø)	⬆️
....ML.AutoML/PipelineSuggesters/PipelineSuggester.cs	83.19% <0%> (-3.37%)	⬇️
...rosoft.ML.AutoML/ColumnInference/TextFileSample.cs	59.6% <0%> (-2.65%)	⬇️
src/Microsoft.ML.Maml/MAML.cs	24.75% <0%> (-1.46%)	⬇️
src/Microsoft.ML.AutoML/Sweepers/Parameters.cs	84.32% <0%> (-0.85%)	⬇️
...ML.Transforms/Text/StopWordsRemovingTransformer.cs	86.1% <0%> (-0.16%)	⬇️
src/Microsoft.ML.Transforms/Text/LdaTransform.cs	84.44% <0%> (-0.16%)	⬇️
....Experimental/OneToOneTransformerBaseExtensions.cs	100% <0%> (ø)
...c/Microsoft.ML.Experimental/MLContextExtensions.cs	0% <0%> (ø)
... and 21 more