gitlab-staging: Remove the namespace alert filtering

The prometheus operator and the helm chart need to be upgraded
to add the option to disable the namespace filtering

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

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: 43.1.0
+    targetRevision: 44.2.0
     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:
@@ -22,6 +22,9 @@ spec:
       values: |
         alertmanager:
           enabled: true  # Temporary for tests
+          alertmanagerSpec:
+            alertmanagerConfigMatcherStrategy:
+              type: None
         defaultRules:
           rules:
             kubeControllerManager: false