Bump cluster applications to v0.40.0

- Bumps runner to 0.25.0
- Bump prometheus to 10.4.1

changelogs/unreleased/upgrade-cluster-applications-v0-40-0.yml

+---
+title: Bump cluster applications CI template to v0.40.0
+merge_request: 53183
+author:
+type: other

lib/gitlab/ci/templates/Managed-Cluster-Applications.gitlab-ci.yml

 apply:
   stage: deploy
-  image: "registry.gitlab.com/gitlab-org/cluster-integration/cluster-applications:v0.37.0"
+  image: "registry.gitlab.com/gitlab-org/cluster-integration/cluster-applications:v0.40.0"
   environment:
     name: production
   variables: