update workflow

.github/workflows/docker-image.yml

@@ -40,3 +40,23 @@ jobs:
     - uses: actions/checkout@v4
     - name: Push the Docker image
       run: docker push ${{ secrets.DOCKERHUB_USERNAME }}/discord-bot
+
+  create_manifest:
+    needs: [build_amd64, build_arm64]
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Log in to Docker Hub
+        uses: docker/login-action@v2
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_PASSWORD }}
+
+      - name: Create and push multi-arch manifest
+        run: |
+          docker pull ${{ secrets.DOCKERHUB_USERNAME }}/your-image-name:amd64
+          docker pull ${{ secrets.DOCKERHUB_USERNAME }}/your-image-name:arm64
+          docker manifest create ${{ secrets.DOCKERHUB_USERNAME }}/your-image-name:latest \
+            --amend ${{ secrets.DOCKERHUB_USERNAME }}/your-image-name:amd64 \
+            --amend ${{ secrets.DOCKERHUB_USERNAME }}/your-image-name:arm64
+          docker manifest push ${{ secrets.DOCKERHUB_USERNAME }}/your-image-name:latest