nit

Author: harupy

pyproject.toml

@@ -23,7 +23,7 @@ profile = 'black'
 src_paths = ['optuna', 'tests', 'docs']
 skip_glob = ['docs/source/conf.py', '**/alembic/versions/*.py']
 line_length = 99
+lines_after_imports = 2
 force_single_line = 'True'
 force_sort_within_sections = 'True'
-lines_after_imports = 2
 order_by_type = 'False'