[Headless] Fix for not receiving any SDL events on Linux (#4182)

* headless: Fix SDL events not working

* Add nuget.config

Ryujinx.Headless.SDL2/Program.cs

@@ -77,7 +77,7 @@ namespace Ryujinx.Headless.SDL2
             _accountManager = new AccountManager(_libHacHorizonManager.RyujinxClient);
             _userChannelPersistence = new UserChannelPersistence();
 
-            if (OperatingSystem.IsMacOS())
+            if (OperatingSystem.IsMacOS() || OperatingSystem.IsLinux())
             {
                 AutoResetEvent invoked = new AutoResetEvent(false);
 
@@ -663,4 +663,4 @@ namespace Ryujinx.Headless.SDL2
             return true;
         }
     }
-}
+}