style: ensure trailing commas in multi-line statements

tests/unit/utils/test_human_readable_list.py

@@ -52,7 +52,7 @@ import pytest
         [1, 2, 3, 42, 'a', 23],
         'and',
         '\'',
-        '\'1\', \'2\', \'3\', \'42\', \'a\' and \'23\''
+        '\'1\', \'2\', \'3\', \'42\', \'a\' and \'23\'',
     ),
 ])
 def test_human_readable_list(ls, final_separator, quotation_mark, expected):