LoadColumn attribute

**System Information (please complete the following information):**
- Model Builder Version (available in Manage Extensions dialog): 16.14.0.2255902
- Visual Studio Version

**Describe the bug**
- On which step of the process did you run into an issue: Model Builder
- Clear description of the problem: When using model builder to train a model, the resulting model input class does not have the loadcolumn attribute, which makes my existing code to consume the ML model (make predictions using data from a .csv file) useless. In previous posts, it was mentioned that this was fixed in versions 16.14.0, however this does not seem to be the case.

**To Reproduce**
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2. Click on '....'
3. Scroll down to '....'
4. See error

**Expected behavior**
A clear and concise description of what you expected to happen.

**Screenshots**
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**Additional context**
Here is a snippet of my code. It fails when I try use LoadFromTextFile.
static void Main(string[] args)
{
Console.WriteLine("Hello World!");

////begin
///

//create mlContext
var mlContext = new MLContext();

//load data from csv file

IDataView testData = mlContext.Data.LoadFromTextFile(testDataPath, separatorChar: ',', hasHeader: true);

// Set-up prediction pipeline
DataViewSchema predictionPipelineSchema;
ITransformer predictionPipeline = mlContext.Model.Load("MLModel.zip", out predictionPipelineSchema);

//apply transformations and generate predictions
IDataView predictions = predictionPipeline.Transform(testData);

//inspect predicted values
var predictionColumn = predictions.GetColumn("PredictedLabel").ToArray();
//IEnumerable scoreColumn = predictions.GetColumn("Score").ToList();

//// Create an IEnumerable of ModelOutput objects from IDataView
IEnumerable predictionsEnumerable =
mlContext.Data.CreateEnumerable(predictions, reuseRowObject: true);

Iniziare esaminando la classe MLModel1.ModelInput generata da Model Builder e la chiamata a LoadFromTextFile mostrata nel report. Riprodurre lo scenario di caricamento CSV in Model Builder e confrontare la classe di input generata con gli attributi necessari per caricare colonne denominate. Il lavoro è completato quando l'input del modello generato supporta il workflow CSV riportato.

Scritto dal modello di indicizzazione a partire dal testo della issue.