A security vulnerability was recently found in the 3.5.0 version of the APISIX Debian-based image.
During further research, it was found that centos7-based APISIX image can no longer pass security scan on dockerhub. Additionally, centos is not being maintained anymore. So it is better to remove the support for the centos7-based APISIX image. But centos7 will not be abandoned completely as the rpm package will still be provided and the CI will still support compatibility testing for centos7.
