Update image used in examples

doc/administration/integration/plantuml.md

@@ -135,7 +135,7 @@ In this basic `docker-compose.yml` file, PlantUML is accessible to GitLab at the
 version: "3"
 services:
   gitlab:
-    image: 'gitlab/gitlab-ee:12.2.5-ee.0'
+    image: 'gitlab/gitlab-ee:17.9.1-ee.0'
     environment:
       GITLAB_OMNIBUS_CONFIG: |
         nginx['custom_gitlab_server_config'] = "location /-/plantuml/ { \n    rewrite ^/-/plantuml/(.*) /$1 break;\n proxy_cache off; \n    proxy_pass  http://plantuml:8005/; \n}\n"