Add ARM build in GitHub Actions

- Hint: Tried to use the plattform parameter of the build-push-action,
   however this failed with an error in the Jobs.
   Therefore, I used a matrix with the platforms.
 - The ARM build takes a long time.

.github/workflows/test-lts-container-images.yaml

@@ -14,10 +14,13 @@ jobs:
           - fpm
     steps:
       - name: 'Check out the repo'
-        uses: actions/checkout@v2
+        uses: actions/checkout@v3
+
+      - name: 'Set up QEMU'
+        uses: docker/setup-qemu-action@v2
 
       - name: 'Set up Docker Buildx'
-        uses: docker/setup-buildx-action@v1
+        uses: docker/setup-buildx-action@v2
 
       - name: 'Build Container images'
         uses: docker/build-push-action@v2