Fix typo in arm64 namespace

.github/workflows/docker-image.yaml

@@ -79,7 +79,7 @@ jobs:
       - name: Build and push Docker image
         uses: docker/build-push-action@v5
         with:
-          platforms: linux/amd64,linux/arm6
+          platforms: linux/amd64,linux/arm64
           context: .
           push: true
           tags: ${{ steps.meta.outputs.tags }}