Remove unused files

osu.Game/Resources/Resource.cs

@@ -1,20 +0,0 @@
-// Copyright (c) 2007-2017 ppy Pty Ltd <contact@ppy.sh>.
-// Licensed under the MIT Licence - https://raw.githubusercontent.com/ppy/osu/master/LICENCE
-
-using System;
-using System.IO;
-using System.Reflection;
-
-namespace osu.Game.Tests.Resources
-{
-    public static class Resource
-    {
-        public static Stream OpenResource(string name)
-        {
-            var localPath = Path.GetDirectoryName(Uri.UnescapeDataString(new UriBuilder(Assembly.GetExecutingAssembly().CodeBase).Path));
-
-            return Assembly.GetExecutingAssembly().GetManifestResourceStream($@"osu.Game.Tests.Resources.{name}") ??
-                Assembly.LoadFrom(Path.Combine(localPath, @"osu.Game.Resources.dll")).GetManifestResourceStream($@"osu.Game.Resources.{name}");
-        }
-    }
-}