dubbo配置端口无效

jdk8
dubbo 3.1.2
-Ddubbo.protocol.port=20887 无效 yml文件中配置也无效，启动后

Start by reproducing the report with JDK 8, Dubbo 3.1.2, -Ddubbo.protocol.port=20887, and the equivalent YAML configuration. Compare the effective startup port with the requested value and use the attached image as the reported result. Done means the configured port 20887 is actually used or the incompatibility is documented.

Written by the indexing model from the issue text.