Code cleanup

Handle scenario where related can contain ".Http.xml;.HttpListener.xml;.Mail.xml;.NameResolution.xml;.NetworkInformation.xml

Author: ocalles

src/Tasks/Microsoft.NET.Build.Tasks/ResolvePackageAssets.cs

@@ -14,6 +14,7 @@
 using NuGet.Common;
 using NuGet.ProjectModel;
 using NuGet.Versioning;
+using static System.Net.Mime.MediaTypeNames;
 
 namespace Microsoft.NET.Build.Tasks
 {
@@ -1165,11 +1166,12 @@ private void WriteDebugItems<T>(
 
                         asset.Properties.TryGetValue(MetadataKeys.RelatedProperty, out string relatedExtensions);
 
-                        foreach (string fileExtension in relatedExtensions.Split(RelatedPropertySeparator))
+                        foreach (string relatedExtension in relatedExtensions.Split(RelatedPropertySeparator))
                         {
-                            if (fileExtension.ToLower() == extension)
+                            string ext = Path.GetExtension(relatedExtension);
+                            if (ext.ToLower() == extension)
                             {
-                                WriteItem(Path.ChangeExtension(itemSpec, extension), library);
+                                WriteItem(Path.ChangeExtension(itemSpec, relatedExtension), library);
                             }
                         }
                     }