Setup poetry correctly for release publish (#138)

.github/workflows/release.yaml

@@ -44,6 +44,16 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
+
+      - name: Set up Python 3.12
+        uses: actions/setup-python@v4
+        with:
+          python-version: "3.12"
+
+      - name: Set up Poetry
+        run: |
+          pip install poetry==${{ env.POETRY_VERSION }}
+
       - name: Publish scenarios to GitHub Pages
         run: |
           poetry run packse index build --no-hash scenarios/*.json