refactor image import and add Alpine docker image

- dynamic import of QR reader
- build docker also for arm64

.github/workflows/ci_docker.yml

@@ -0,0 +1,76 @@
+name: "Docker: build and publish"
+
+# How to setup: https://event-driven.io/en/how_to_buid_and_push_docker_image_with_github_actions/
+# How to run: https://aschmelyun.com/blog/using-docker-run-inside-of-github-actions/
+
+on:
+  # run it on push to the default repository branch
+  push:
+  #  branches: [master]
+  # run it during pull request
+  # pull_request:
+
+jobs:
+  # define job to build and publish docker image
+  build-and-push-docker-image:
+    name: Build Docker image and push to repositories
+    # run only when code is compiling and tests are passing
+    runs-on: ubuntu-latest
+
+    # steps to perform in job
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+
+      # setup Docker build action
+      - name: Set up Docker Buildx
+        id: buildx
+        uses: docker/setup-buildx-action@v2
+
+      - name: Login to DockerHub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Login to Github Packages
+        uses: docker/login-action@v2
+        with:
+          registry: ghcr.io
+          username: ${{ github.actor }}
+          password: ${{ secrets.GHCR_IO_TOKEN }}
+
+      - name: "no_qr_reader: Build image and push to Docker Hub and GitHub Container Registry"
+        uses: docker/build-push-action@v2
+        with:
+          # relative path to the place where source code with Dockerfile is located
+          platforms: linux/amd64,linux/arm64
+          context: .
+          file: Dockerfile_no_qr_reader
+          # Note: tags has to be all lower-case
+          tags: |
+            scit0/extract_otp_secret_keys_no_qr_reader:latest
+            ghcr.io/scito/extract_otp_secret_keys_no_qr_reader:latest
+          # build on feature branches, push only on master branch
+          # TODO push: ${{ github.ref == 'refs/heads/master' }}
+          push: true
+
+      - name: "qr_reader: Build image and push to Docker Hub and GitHub Container Registry"
+        uses: docker/build-push-action@v2
+        with:
+          platforms: linux/amd64,linux/arm64
+          # relative path to the place where source code with Dockerfile is located
+          context: .
+          # Note: tags has to be all lower-case
+          tags: |
+            scit0/extract_otp_secret_keys:latest
+            ghcr.io/scito/extract_otp_secret_keys:latest
+          # build on feature branches, push only on master branch
+          # TODO push: ${{ github.ref == 'refs/heads/master' }}
+          push: true
+
+      - name: Image digest
+        run: echo ${{ steps.docker_build.outputs.digest }}