fix: remove create buildx

Author: zzswang

Dockerfile

@@ -24,5 +24,5 @@ RUN BUILDX_VERSION=$(curl -s "https://api.github.com/repos/docker/buildx/release
   chown -R runner:runner /home/runner/.docker && \
   chmod -R 755 /home/runner/.docker
 
-# Create a default buildx builder that supports cache
+# Create buildx builder (will be recreated at runtime if needed)
 RUN sudo -u runner docker buildx create --name container --driver docker-container --use --bootstrap || true