ci: update flake8 args

.github/workflows/test.yml

@@ -36,7 +36,7 @@ jobs:
         # stop the build if there are Python syntax errors or undefined names
         flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
         # exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
-        flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
+        flake8 . --count --extend-ignore=E203,F401 --exit-zero --max-line-length=88 --statistics --exclude _deprecated
     - name: Test with pytest
       run: |
         pytest