fix example

Author: jvanbrunschot

examples/complete-postgres/main.tf

@@ -169,7 +169,7 @@ ephemeral "aws_secretsmanager_secret_version" "db_password" {
 module "db_write_only" {
   source = "../../"
 
-  identifier = local.name
+  identifier = "${local.name}-write-only"
 
   # All available versions: https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/CHAP_PostgreSQL.html#PostgreSQL.Concepts
   engine                   = "postgres"
@@ -179,6 +179,8 @@ module "db_write_only" {
   major_engine_version     = "14"         # DB option group
   instance_class           = "db.t4g.large"
 
+  allocated_storage = 20
+
   # NOTE: Do NOT use 'user' as the value for 'username' as it throws:
   # "Error creating DB Instance: InvalidParameterValue: MasterUsername
   # user cannot be used as it is a reserved word used by the engine"