Add linting rule

.github/workflows/test.yml

@@ -3,6 +3,26 @@ name: Tests
 on: [ push, pull_request ]
 
 jobs:
+
+  lint:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Set up Python
+        uses: actions/setup-python@v2
+        with:
+          python-version: "3.11"
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install ruff
+
+      - name: Lint with Ruff
+        run: ruff .
+
   test:
 
     name: Test on Python ${{ matrix.python-version }}