we need to remove more xiaomi refs in the Apache Ozhera code

https://github.com/apache/ozhera/blob/66402b2a2b33712fa060efe7aa2f254bb32922cb/ozhera-prometheus-agent/ozhera-prometheus-agent-server/Dockerfile#L17

https://github.com/apache/ozhera/blob/66402b2a2b33712fa060efe7aa2f254bb32922cb/ozhera-demo-client/ozhera-demo-client-server/src/main/proto/MyService.proto#L25

https://github.com/apache/ozhera/blob/66402b2a2b33712fa060efe7aa2f254bb32922cb/readme/custom-tracking/custom-tracking.md?plain=1#L30

https://github.com/search?q=repo%3Aapache%2Fozhera+%22package+com.xiaomi.youpin%22&type=code

https://github.com/search?q=repo%3Aapache%2Fozhera%20xiaomi&type=code