Merge pull request #9530 from id/ci-update-docker-hub-short-description

ci: update short description on docker hub page for emqx/emqx

.github/workflows/build_and_push_docker_images.yaml

@@ -188,6 +188,7 @@ jobs:
         password: ${{ secrets.DOCKERHUB_PASSWORD }}
         repository: "emqx/${{ needs.prepare.outputs.BUILD_PROFILE }}"
         readme-filepath: ./source/deploy/docker/README.md
+        short-description: "The most scalable open-source MQTT broker for IoT, IIoT, connected vehicles, and more."
 
   docker-elixir:
     runs-on: ${{ matrix.arch[1] }}