vault cluster min_size make smaller

min_size cluster will now be calculated as `(({cluster_size}/3)+1)`

modules/vault-cluster/main.tf

@@ -25,7 +25,7 @@ resource "aws_autoscaling_group" "autoscaling_group" {
   vpc_zone_identifier = var.subnet_ids
 
   # Use a fixed-size cluster
-  min_size             = floor(var.cluster_size / 3) < 1 ? 1 : floor(var.cluster_size / 3)*3
+  min_size             = floor(var.cluster_size / 3) < 1 ? 1 : floor(var.cluster_size / 3) + 1
   max_size             = (var.cluster_size * 2) + 1
   desired_capacity     = var.cluster_size
   termination_policies = [var.termination_policies]