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Co-authored-by: c-bata <c-bata@users.noreply.github.com>

.github/workflows/python-coverage.yml

@@ -28,7 +28,6 @@ jobs:
         python -m pip install --progress-bar off --upgrade pip setuptools
         pip install --progress-bar off .[optional]
         pip install --progress-bar off .[test]
-        pip install --progress-bar off "optuna>=3.1.0"
         pip install --progress-bar off .
         echo 'import coverage; coverage.process_startup()' > sitecustomize.py
     - name: Tests