Fix flake8 linting issues

testing/conftest.py

@@ -2,7 +2,6 @@ import glob
 import os
 import subprocess
 from subprocess import CalledProcessError
-import traceback
 
 import pytest
 

testing/test_custom_tjas.py

@@ -48,4 +48,4 @@ def test_converted_custom_tjas(path_tja, tmp_path, entry_point):
                        key=lambda s: [order.index(c) if c in order
                                       else len(order) for c in s])
     for path_out in paths_out:
-        parse_fumen(path_out, exclude_empty_measures=False)
+        parse_fumen(path_out, exclude_empty_measures=False)