Add github action workflow to publish latest

.github/workflows/publish.yaml

@@ -0,0 +1,24 @@
+name: Publish Docker image
+
+on:
+  push:
+    branches:
+      - master
+
+jobs:
+  push_to_registry:
+    name: Push Docker image to Docker Hub
+    runs-on: ubuntu-latest
+    steps:
+      - name: Log in to Docker Hub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+      - name: Build and push Docker image
+        uses: docker/build-push-action@v3
+        with:
+          push: true
+          tags: crocmagnon/blog:latest
+          build-args: |
+            POETRY_OPTIONS="--no-dev"