Remove jenkins update center component

Created by: LinuxSuRen

Don't need Jenkins update-center anymore. We can package all plugins with Jenkins core into a docker image. I started a new project which can archive that. So once I confirm it's ok. Please fork this project into kubesphere org. After that, I will remove my project.

These changes are dependent on the following upstream PRs:

• https://github.com/jenkins-zh/jenkins-cli/pull/458 was merged

References

• https://github.com/kubesphere/ks-jenkins/
• https://github.com/jenkinsci/custom-war-packager