Update tests/by-util/test_od.rs

Co-authored-by: Daniel Hofstetter <[email protected]>

Author: sylvestre

tests/by-util/test_od.rs

@@ -1033,7 +1033,7 @@ fn test_od_strings_option() {
         .arg("-S11")
         .pipe_in(b"          \x00")
         .succeeds()
-        .stdout_is("");
+        .no_output();
 
     // Test with no address prefix (-An)
     new_ucmd!()