Add a GitHub Actions workflow to build and test Docker images for multiple Python versions.

.github/workflows/docker-test.yml

@@ -0,0 +1,27 @@
+name: Docker Build Test
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    strategy:
+      matrix:
+        python-version: ["3.10", "3.11", "3.12", "3.13"]
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v5
+      with:
+        python-version: ${{ matrix.python-version }}
+    - name: Build Docker Image
+      run: docker build . --file Dockerfile --build-arg PYTHON_VERSION=${{ matrix.python-version }} --tag lxmfy-test:${{ matrix.python-version }}