CentOS 7 is EOL

[caigy]

CentOS 7, which is the base docker image of Apache RocketMQ, reached end of life (EOL) on June 30, 2024. After that, no further updates will be provided and yum-repo will be not available as reported in #107 .

Furthermore, CentOS 7-based images will be removed from Docker official images on July 16.

As a result, we have to replace CentOS 7 with a new OS in docker image of Apache RocketMQ.