feat request: support consumergroup  management in admin interface

**FEATURE REQUEST**

We're developing a CLI tool designed to efficiently manage RocketMQ clusters, both in self-hosted environments and across various cloud providers, but currently the go sdk is missing some critical features like

https://github.com/apache/rocketmq-client-go/blob/master/admin/admin.go#L39

1. getting cluster info
2. managing consumer group