Apply suggestions from code review

Co-authored-by: Hugo van Kemenade <[email protected]>

Author: Yay295

Tests/test_image_filter.py

@@ -52,7 +52,7 @@ def test_crash(size):
 
 
 @pytest.mark.parametrize(
-    "mode,expected",
+    "mode, expected",
     (
         ("1", (4, 0)),
         ("L", (4, 0)),