chore(tests): add 'dfgi' to spell-checker ignore list in test_sort.rs

This update prevents spell-check warnings for 'dfgi', which appears as a test term in the sort utility tests, ensuring consistent linting without flagging non-standard words.

Author: mattsu2020

tests/by-util/test_sort.rs

@@ -3,7 +3,7 @@
 // For the full copyright and license information, please view the LICENSE
 // file that was distributed with this source code.
 
-// spell-checker:ignore (words) ints (linux) NOFILE
+// spell-checker:ignore (words) ints (linux) NOFILE　dfgi
 #![allow(clippy::cast_possible_wrap)]
 
 use std::env;