Merge branch 'tkuah-gdk-multiple-new-config' into 'master'

Switch to new GDK config for multiple databases

See merge request gitlab-org/gitlab!82267

doc/development/database/multiple_databases.md

@@ -40,7 +40,9 @@ If you are using GDK, you can follow the following steps:
    ```yaml
    gitlab:
      rails:
-       multiple_databases: true
+       databases:
+         ci:
+           enabled: true
    ```
 
 1. Reconfigure GDK: