chore: remove unused action in docker ci task

.github/workflows/ci-docker.yaml

@@ -20,15 +20,9 @@ jobs:
           images: moonrailgun/tianji
           tags: |
             type=sha
-      - name: Login to DockerHub
-        if: github.event_name != 'pull_request'
-        uses: docker/login-action@v3
-        with:
-          username: ${{ secrets.DOCKERHUB_USERNAME }}
-          password: ${{ secrets.DOCKERHUB_TOKEN }}
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
-      - name: Build and push
+      - name: Build
         uses: docker/build-push-action@v5
         with:
           # context: .