fix: Correct service principal to rds.amazonaws.com (incl China)

main.tf

@@ -6,7 +6,11 @@ locals {
 
 data "aws_region" "current" {}
 data "aws_partition" "current" {}
-
+data "aws_service_principal" "rds" {
+  count = var.create && var.create_iam_role ? 1 : 0
+  service_name = "rds"
+  region = data.aws_region.current.name
+}
 ################################################################################
 # RDS Proxy
 ################################################################################
@@ -111,7 +115,7 @@ data "aws_iam_policy_document" "assume_role" {
 
     principals {
       type        = "Service"
-      identifiers = ["rds.${data.aws_partition.current.dns_suffix}"]
+      identifiers = [data.aws_service_principal.rds[0].name]
     }
   }
 }