Provide packages for SUSE Linux Enterprise Server SLES 15.7

SLES 15.7 was released on 17 Jun 2025, but there are no GitLab packages for it yet. the latest versions available at https://packages.gitlab.com/app/gitlab/gitlab-ee are for 15.6.

It seems that packages for 15.6 are working fine on 15.7 but since SUSE ist ending general support for 15.6 on 28 Nov 2025 it would be good to have supported GitLab packages for 15.7