Update pythonpackage.yml to use poetry

.github/workflows/pythonpackage.yml

@@ -14,28 +14,32 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.10", "3.11", "3.12"]
+        python-version: ["3.10", "3.11", "3.12", "3.x"] # pythonpublish.yml uses "3.x".
 
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
+
+      - name: Install poetry
+        run: |
+          pipx install poetry==${{ POETRY_VERSION }}
 
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v3
+        uses: actions/setup-python@v4
         with:
           python-version: ${{ matrix.python-version }}
+          cache: 'poetry'
 
       - name: Install dependencies
         run: |
-          python -m pip install --upgrade pip
-          pip install -e .[dev]
+          poetry install
 
       - name: Lint
         run: |
-          black --check .
-          mypy .
+          poetry run black --check .
+          poetry run mypy .
 
       - name: Test with pytest
         run: |
-          pytest
+          poetry run pytest
         env:
           ENVIRONMENT: local