Merge branch 'fix/doc-administration-maintenance-mode' into 'master'

Doc Consistency: administration/maintenance_mode

See merge request gitlab-org/gitlab!69668

doc/administration/maintenance_mode/index.md

@@ -6,7 +6,7 @@ info: To determine the technical writer assigned to the Stage/Group associated w
 
 # GitLab Maintenance Mode **(PREMIUM SELF)**
 
-> [Introduced](https://gitlab.com/groups/gitlab-org/-/epics/2149) in GitLab Premium 13.9.
+> [Introduced](https://gitlab.com/groups/gitlab-org/-/epics/2149) in GitLab 13.9.
 
 Maintenance Mode allows administrators to reduce write operations to a minimum while maintenance tasks are performed. The main goal is to block all external actions that change the internal state, including the PostgreSQL database, but especially files, Git repositories, Container repositories, and so on.