Merge pull request #128055 from Synthetica9/sway-check-quit

nixos/tests/sway: add check that sway quits

nixos/tests/sway.nix

···
 
     # Exit Sway and verify process exit status 0:
     machine.succeed("su - alice -c 'swaymsg exit || true'")
+    machine.wait_until_fails("pgrep -x sway")
+
     # TODO: Sway currently segfaults after "swaymsg exit" but only in this VM test:
     # machine # [  104.090032] sway[921]: segfault at 3f800008 ip 00007f7dbdc25f10 sp 00007ffe282182f8 error 4 in libwayland-server.so.0.1.0[7f7dbdc1f000+8000]
     # machine.wait_for_file("/tmp/sway-exit-ok")