test: update to latest postresql module version (#428)

SKIP UPGRADE TEST

Due to a deprecation of certain ICD parameters in the IBM provider, the older versions of these examples will fail always. Skipping this upgrade test as it is expected to fail

Author: toddgiguere

examples/default/main.tf

@@ -73,7 +73,7 @@ module "vpe_security_group" {
 
 module "postgresql_db" {
   source            = "terraform-ibm-modules/icd-postgresql/ibm"
-  version           = "3.8.3"
+  version           = "3.9.0"
   resource_group_id = module.resource_group.resource_group_id
   name              = "${var.prefix}-vpe-pg"
   region            = var.region