Fix windows console runner update crash (#1670)

* Kill node process to recover handle

So we can print to the console in Runner.Listener once again

* Revert testing changes

Co-authored-by: Ferenc Hammerl <hammerl.ferenc@gmail.com>

src/Runner.Listener/SelfUpdater.cs

@@ -1060,6 +1060,8 @@ namespace GitHub.Runner.Listener
                                               arguments: $"\"{hashFilesScript.Replace("\"", "\\\"")}\"",
                                               environment: env,
                                               requireExitCodeZero: false,
+                                              outputEncoding: null,
+                                              killProcessOnCancel: true,
                                               cancellationToken: token);
 
                 if (exitCode != 0)