Merge branch 'geo-remove-source-installs-mention-docs' into 'master'

Remove note about omnibus-only installation

See merge request gitlab-org/gitlab!18084

doc/administration/geo/replication/database.md

 # Geo database replication **(PREMIUM ONLY)**
 
-NOTE: **Note:**
-The following steps are for Omnibus installs only. Using Geo with source-based installs was **deprecated** in GitLab 11.5.
-
 NOTE: **Note:**
 If your GitLab installation uses external (not managed by Omnibus) PostgreSQL
 instances, the Omnibus roles will not be able to perform all necessary