added ruff test

shared/tests/test_playback.py

@@ -7,16 +7,12 @@ that the policy's risks are reported instead of discovered later.
 
 from __future__ import annotations
 
-import csv
 import json
 import shutil
-import sys
-import types
 from pathlib import Path
 
 import numpy as np
 import pytest
-
 from orisys_app_shared.acquisition.sdk_worker import SdkPacket
 from orisys_app_shared.record import (
     ExperimentRecorder,