Ignore test_ispeed_ospeed_valid_speeds for issue #9547

on different platforms the output is different due to different versions so cannot use this as a test.

Author: ChrisDryden

tests/by-util/test_stty.rs

@@ -529,6 +529,7 @@ fn test_saved_state_with_control_chars() {
 
 #[test]
 #[cfg(unix)]
+#[ignore = "Issue: #9547"]
 fn test_ispeed_ospeed_valid_speeds() {
     let (path, _controller, _replica) = pty_path();
     let (_at, ts) = at_and_ts!();