Update docker Docker tag to v28

This MR contains the following updates:

Package	Update	Change
docker	major	25.0 -> 28.1
docker	major	25-dind -> 28-dind

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testserver/docker_gitlab/templates/docker-compose.yml

@@ -34,7 +34,7 @@ services:
 
   dind:
 
-    image: docker:25-dind
+    image: docker:28-dind
     restart: always
     privileged: true
     environment: