chore: sync template versions with image updates

library/compose/gitlab/template.yaml

@@ -23,7 +23,7 @@ metadata:
   icon:
     provider: selfh
     id: gitlab
-  version: 18.6.2-ce.0
+  version: 18.6.3-ce.0
   author: Christian Lempa
   date: '2026-01-07'
   tags: