Fix kube-prometheus-stack manifests

Updates the HelmRepository and HelmRelease to remove chart
verification and switch to using the official HTTPS repository
at https://prometheus-community.github.io/helm-charts.

OCI builds have temporarily been suspended for these charts due
to pipeline errors.

See: prometheus-community/helm-charts#2841

Signed-off-by: Alex Howard <thezanke@gmail.com>

manifests/monitoring/kube-prometheus-stack/release.yaml

@@ -11,8 +11,6 @@ spec:
       sourceRef:
         kind: HelmRepository
         name: prometheus-community
-      verify:
-        provider: cosign
       interval: 60m
   install:
     crds: Create

manifests/monitoring/kube-prometheus-stack/repository.yaml

@@ -4,5 +4,6 @@ metadata:
   name: prometheus-community
 spec:
   interval: 120m
-  type: oci
-  url: oci://ghcr.io/prometheus-community/charts
+  # OCI builds for kube-prometheus-stack have been temporarily disabled (see https://github.com/prometheus-community/helm-charts/issues/2940).
+  type: default
+  url: https://prometheus-community.github.io/helm-charts