Update grafana.tf

Author: akananth

nap/grafana.tf

@@ -1,5 +1,5 @@
 resource "helm_release" "grafana" {
-  name = format("%s-gfa-%s", lower(local.project_prefix), lower(local.build_suffix))
+  name = format("%s-gfa-%s", lower(local.prefix), lower(local.build_suffix))
   repository = "https://grafana.github.io/helm-charts"
   chart = "grafana"
   version = "6.50.7"