Add Action publish-docker-image.yml

Author: tschaffter

.github/workflows/publish-docker-image.yml

@@ -0,0 +1,22 @@
+name: Publish Docker Image
+
+on:
+  push:
+    branches:
+    - 'releases/**'
+
+jobs:
+  publish-docker-image:
+    runs-on: ubuntu-18.04
+
+    steps:
+    - uses: actions/checkout@v2
+
+    - name: Publish Docker image
+      uses: docker/build-push-action@v1
+      with:
+        username: ${{ secrets.DOCKER_USERNAME }}
+        password: ${{ secrets.DOCKER_PASSWORD }}
+        repository: tschaffter/${{ github.event.repository.name }}
+        tag_with_ref: true
+        push: ${{ startsWith(github.ref, 'refs/heads/') }}