Merge branch 'collen-master-patch-34865' into 'master'

Add warning alert box for Praefect

See merge request gitlab-org/gitlab!68539

doc/administration/gitaly/praefect.md

@@ -353,6 +353,7 @@ If there are multiple Praefect nodes:
 
 To complete this section you need a [configured PostgreSQL server](#postgresql), including:
 
+WARNING:
 Praefect should be run on a dedicated node. Do not run Praefect on the
 application server, or a Gitaly node.