Add github action for test

.github/workflows/python-app.yml

@@ -0,0 +1,34 @@
+name: Python package
+
+on:
+  push:
+    branches: ["master"]
+  pull_request:
+    branches: ["master"]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.8", "3.9", "3.10", "3.11"]
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v3
+        with:
+          python-version: ${{ matrix.python-version }}
+      - name: Install dependencies
+        run: |
+          sudo apt install -y ledger hledger
+          python -m pip install --upgrade pip
+          python -m pip install --upgrade poetry
+          python -m pip install flake8 pytest
+          poetry install
+      - name: Lint with black
+        run: |
+          black --check .
+      - name: Test with pytest
+        run: |
+          poetry run python -m pytest