CLI samples command line parameters should be updated

[dliedke]

Current CLI samples at https://github.com/dotnet/machinelearning-samples/tree/main/samples/CLI/MulticlassClassification_CLI

Show command line sample: mlnet auto-train --task multiclass-classification --dataset corefx-issues-train.tsv --label-column-name Area --max-exploration-time 300

But it doesn't work anymore. This is the new command line parameters for the current version: mlnet classification --dataset corefx-issues-train.tsv --label-col Area --train-time 300

This is the version I am using: mlnet --version 16.13.5+936af07a091757189faee78de128429bf06a6845

Thanks!