Fix slnf Headless path

Avalonia.Desktop.slnf

@@ -23,8 +23,6 @@
       "src\\Avalonia.Dialogs\\Avalonia.Dialogs.csproj",
       "src\\Avalonia.Fonts.Inter\\Avalonia.Fonts.Inter.csproj",
       "src\\Avalonia.FreeDesktop\\Avalonia.FreeDesktop.csproj",
-      "src\\Avalonia.Headless.Vnc\\Avalonia.Headless.Vnc.csproj",
-      "src\\Avalonia.Headless\\Avalonia.Headless.csproj",
       "src\\Avalonia.MicroCom\\Avalonia.MicroCom.csproj",
       "src\\Avalonia.Native\\Avalonia.Native.csproj",
       "src\\Avalonia.OpenGL\\Avalonia.OpenGL.csproj",
@@ -33,6 +31,8 @@
       "src\\Avalonia.Themes.Fluent\\Avalonia.Themes.Fluent.csproj",
       "src\\Avalonia.Themes.Simple\\Avalonia.Themes.Simple.csproj",
       "src\\Avalonia.X11\\Avalonia.X11.csproj",
+      "src\\Headless\\Avalonia.Headless.Vnc\\Avalonia.Headless.Vnc.csproj",
+      "src\\Headless\\Avalonia.Headless\\Avalonia.Headless.csproj",
       "src\\Linux\\Avalonia.LinuxFramebuffer\\Avalonia.LinuxFramebuffer.csproj",
       "src\\Markup\\Avalonia.Markup.Xaml.Loader\\Avalonia.Markup.Xaml.Loader.csproj",
       "src\\Markup\\Avalonia.Markup.Xaml\\Avalonia.Markup.Xaml.csproj",
@@ -65,4 +65,4 @@
       "tests\\Avalonia.UnitTests\\Avalonia.UnitTests.csproj"
     ]
   }
-}
+}