Jenkins Update Center: brownout #4 for 24 hours Jenkins

[Damien Duportal]

Hello dear users and contributors,

As described in https://www.jenkins.io/blog/2024/09/25/update-center-brownouts-4/, we are starting another 24 hour brownout on the Update Center.

We expect no incident this time as we added full HTTP-only support but we never know.

For the Jenkins Infra team,

Damien Duportal