[#314] Format all files with black and isort

Signed-off-by: Vladimir Domnich <v.domnich@yadro.com>

pytest_tests/helpers/s3_helper.py

@@ -1,7 +1,7 @@
 from typing import Optional
 
 import allure
-import pytest
+
 from steps import s3_gate_bucket, s3_gate_object