Add github workflow

.github/workflows/tox.yaml

@@ -0,0 +1,24 @@
+name: Run tox
+
+on:
+  - push
+  - pull_request
+
+jobs:
+  tox:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: ['3.9', '3.10', '3.11']
+
+    steps:
+    - uses: actions/checkout@v3
+    - name: Set up PDM
+      uses: pdm-project/setup-pdm@v2
+      with:
+        python-version: ${{ matrix.python-version }}
+    - name: Install dependencies
+      run: |
+        pdm install -d -G test -G lint
+    - name: Test with tox
+      run: pdm run tox