Fix issue probably-meant-fstring found at https://codereview.doctor (a…

…pache#19826)

superset/db_engine_specs/presto.py

@@ -1198,7 +1198,7 @@ def latest_sub_partition(
         part_fields = indexes[0]["column_names"]
         for k in kwargs.keys():  # pylint: disable=consider-iterating-dictionary
             if k not in k in part_fields:  # pylint: disable=comparison-with-itself
-                msg = "Field [{k}] is not part of the portioning key"
+                msg = f"Field [{k}] is not part of the portioning key"
                 raise SupersetTemplateException(msg)
         if len(kwargs.keys()) != len(part_fields) - 1:
             msg = (