[Task] recovery etcd sync

### Description

Due to issues with the previously used etcd Docker image, which caused frequent e2e test failures, I have temporarily removed the etcd sync method. I hope to restore the related synchronization logic after updating to a stable image.

### Task List

1. use stable image to replace old etcd image
2. recovery etcd sync

No files, tests, or entry points are named. Start by locating the Docker image configuration and the removed etcd synchronization implementation, then check the existing end-to-end setup. Done means a stable image replaces the old one, etcd sync is restored, and the related e2e failures no longer occur.

Written by the indexing model from the issue text.