fix c# single file output due to invalid output path

Il2CppInspector.Redux.GUI/Outputs/CSharpStubOutput.cs

@@ -44,13 +44,15 @@ public class CSharpStubOutput : IOutputFormatProvider
 
         await client.ShowLogMessage("Writing C# type definitions");
 
+        var outputPathFile = Path.Join(outputPath, "il2cpp.cs");
+
         switch (settings.Layout, settings.SortingMode)
         {
             case (CSharpLayout.SingleFile, TypeSortingMode.TypeDefinitionIndex):
-                writer.WriteSingleFile(outputPath, info => info.Index);
+                writer.WriteSingleFile(outputPathFile, info => info.Index);
                 break;
             case (CSharpLayout.SingleFile, TypeSortingMode.Alphabetical):
-                writer.WriteSingleFile(outputPath, info => info.Name);
+                writer.WriteSingleFile(outputPathFile, info => info.Name);
                 break;
             
             case (CSharpLayout.Namespace, TypeSortingMode.TypeDefinitionIndex):

Il2CppInspector.Redux.GUI/UiContext.cs

@@ -107,6 +107,7 @@ public class UiContext
                 // Clear out failed metadata and binary so subsequent loads do not use any stale data.
                 _metadata = null;
                 _binary = null;
+
                 return false;
             }
         }