Skip unit test with optuna version

.github/workflows/python-tests.yml

@@ -70,3 +70,22 @@ jobs:
       - name: Run python unit tests
         run: |
           pytest python_tests
+  test-with-optuna-oldest:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Setup Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.11'
+          architecture: x64
+      - name: Install dependencies
+        run: |
+          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 .
+          python -m pip install --progress-bar off --force-reinstall optuna==3.1.0
+      - name: Run python unit tests
+        run: |
+          pytest python_tests