Remove OnPrepareDetectionAsync method and related skipped folder logic from DockerfileComponentDetector

Author: jpinz

src/Microsoft.ComponentDetection.Detectors/dockerfile/DockerfileComponentDetector.cs

@@ -3,8 +3,6 @@ namespace Microsoft.ComponentDetection.Detectors.Dockerfile;
 using System;
 using System.Collections.Generic;
 using System.IO;
-using System.Linq;
-using System.Reactive.Linq;
 using System.Threading;
 using System.Threading.Tasks;
 using Microsoft.ComponentDetection.Common;
@@ -46,13 +44,6 @@ public DockerfileComponentDetector(
 
     protected override IList<string> SkippedFolders => ["node_modules"];
 
-    protected override Task<IObservable<ProcessRequest>> OnPrepareDetectionAsync(
-        IObservable<ProcessRequest> processRequests,
-        IDictionary<string, string> detectorArgs,
-        CancellationToken cancellationToken = default) =>
-        Task.FromResult(processRequests.Where(processRequest =>
-            !this.IsInSkippedFolder(processRequest.ComponentStream.Location)));
-
     protected override async Task OnFileFoundAsync(ProcessRequest processRequest, IDictionary<string, string> detectorArgs, CancellationToken cancellationToken = default)
     {
         var singleFileComponentRecorder = processRequest.SingleFileComponentRecorder;
@@ -81,12 +72,6 @@ protected override async Task OnFileFoundAsync(ProcessRequest processRequest, ID
         }
     }
 
-    private bool IsInSkippedFolder(string filePath)
-    {
-        var pathSegments = filePath.Split(['/', '\\'], StringSplitOptions.RemoveEmptyEntries);
-        return this.SkippedFolders.Any(skippedFolder => pathSegments.Contains(skippedFolder, StringComparer.OrdinalIgnoreCase));
-    }
-
     private Task ParseDockerFileAsync(string fileContents, string fileLocation, ISingleFileComponentRecorder singleFileComponentRecorder, Dictionary<string, string> stageNameMap)
     {
         var dockerfileModel = Dockerfile.Parse(fileContents);