Fixup tests.

Author: michaelnebel

csharp/extractor/Semmle.Extraction.Tests/OverlayInfo.cs

@@ -1,6 +1,6 @@
 using Xunit;
-using Semmle.Util;
 using Semmle.Extraction.CSharp;
+using System.IO;
 
 namespace Semmle.Extraction.Tests
 {
@@ -23,9 +23,9 @@ public void TestOverlay()
             var overlay = new OverlayInfo(logger, "overlay/source/path", json);
 
             Assert.True(overlay.IsOverlayMode);
-            Assert.False(overlay.OnlyMakeScaffold("overlay/source/path/app/controllers/about_controller.xyz"));
-            Assert.False(overlay.OnlyMakeScaffold("overlay/source/path/app/models/about.xyz"));
-            Assert.True(overlay.OnlyMakeScaffold("overlay/source/path/app/models/unchanged.xyz"));
+            Assert.False(overlay.OnlyMakeScaffold("overlay/source/path" + Path.DirectorySeparatorChar + "app/controllers/about_controller.xyz"));
+            Assert.False(overlay.OnlyMakeScaffold("overlay/source/path" + Path.DirectorySeparatorChar + "app/models/about.xyz"));
+            Assert.True(overlay.OnlyMakeScaffold("overlay/source/path" + Path.DirectorySeparatorChar + "app/models/unchanged.xyz"));
         }
     }
 }