chore(deps): update helm release prometheus-snmp-exporter to v1.8.1

Author: renovate[bot]

k8s-manifests/apps/cluster-wide-app-resources/prometheus-snmp-exporter.yaml

@@ -10,7 +10,7 @@ spec:
   source:
     chart: prometheus-snmp-exporter
     repoURL: https://prometheus-community.github.io/helm-charts
-    targetRevision: 1.5.0
+    targetRevision: 1.8.1
     helm:
       releaseName: prometheus-snmp-exporter
       # https://github.com/prometheus-community/helm-charts/blob/main/charts/prometheus-snmp-exporter/values.yaml