Fix test again

Author: benoit74

tests/test_libzim_creator.py

@@ -375,7 +375,7 @@ def test_creator_additem(fpath, lipsum_item):
             c.add_item("hello")  # pyright: ignore [reportCallIssue, reportArgumentType]
         with pytest.raises(
             TypeError,
-            match="got an unexpected keyword argument: 'mimetype'",
+            match="got an unexpected keyword argument 'mimetype'",
         ):
             c.add_item(mimetype="text/html")  # pyright: ignore [reportCallIssue]