gitlab-staging: upgrade prometheus to first version without namespace filtering

Let's try if it solve something on the namespace alert filtering

Related to swh/infra/sysadm-environment#5281
Related to swh/infra/sysadm-environment#5036 too

argocd-configuration/applications/gitlab-staging/prometheus-application.yaml

@@ -10,7 +10,7 @@ spec:
   source:
     chart: kube-prometheus-stack
     repoURL: https://prometheus-community.github.io/helm-charts
-    targetRevision: 41.4.0
+    targetRevision: 43.1.0
     helm:
       releaseName: gitlab-staging-prometheus # must match the application name (https://github.com/argoproj/argo-cd/issues/2871)
       # The crds must be manually applied to avoid the following error: