Add test workflow to run pytest in CI

Author: hnez

.github/workflows/test.yml

@@ -0,0 +1,29 @@
+name: Test
+
+on: [pull_request, push]
+
+jobs:
+  test:
+    name: Test
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v7
+
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install pytest pyyaml requests
+
+      - name: Unpack action
+        run: python tools/unpack.py
+
+      - name: Run pytest
+        run: python -m pytest tests/
+
+      - name: Pack action
+        run: python tools/pack.py
+
+      - name: Check for changes
+        run: git diff --exit-code