openSUSE Leap 15.4 will have its EOL on at end of November 2023. In GitLab 16.4 we introduced supported OpenSUSE 15.5 packages. We should: * [x] Add deprecation note for the OpenSUSE 15.4 package https://gitlab.com/gitlab-org/gitlab/-/merge_requests/132050 * [x] Add deprecation to the omnibus package https://gitlab.com/gitlab-org/omnibus-gitlab/-/merge_requests/7154