Add workflow for testing on different platforms

.github/workflows/test.yaml

@@ -0,0 +1,36 @@
+name: Test
+on: [push, pull_request]
+
+jobs:
+  test:
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.11"]
+        poetry-version: ["1.5.0"]
+        os: [ubuntu-latest, macos-latest, windows-latest]
+    runs-on: ${{ matrix.os }}
+    env: 
+      FLASK_SECRET_KEY: ${{ secrets.FLASK_SECRET_KEY }}
+    steps:
+      - name: Clone the project
+        uses: actions/checkout@v3
+
+      - name: Install Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Upgrade pip
+        run: python -m pip install -U pip
+
+      - name: Install Poetry
+        uses: abatilo/actions-poetry@v2
+        with:
+          poetry-version: ${{ matrix.poetry-version }}
+
+      - name: Install project
+        run: poetry install --no-root
+
+      - name: Run tests
+        run: poetry run task test