Add an action for testing

+name: Run Tests
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  build-linux:
+    strategy:
+      matrix:
+        python-version: ["3.10"]
+    runs-on: "ubuntu-latest"
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          python-version: ${{ matrix.python-version }}
+      - name: Install Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: ${{ matrix.python-version }}
+      - name: Remove development dependencies
+        run: sed -i '/\[tool.poetry.group.dev.dependencies\]/,/\[/d' pyproject.toml
+      - name: Install Poetry
+        uses: snok/install-poetry@v1
+        with:
+          version: 1.2.2
+          virtualenvs-in-project: true
+      - name: Install dependencies
+        run: poetry install --no-interaction --no-root --without=dev
+      - name: Install library
+        run: poetry install --no-interaction --without=dev
+      - name: Install development tools
+        run: poetry add gmpg
+      - name: Run tests
+        run: poetry run pytest --doctest-modules
+      - uses: psf/black@stable
+        with:
+          options: "--check --verbose"
+          src: "."
+          version: "23.7"
+      - uses: isort/isort-action@v1