fix(dataabse): restrict outbound traffic to private subnets

Author: lrasata

terraform/layers/database/main.tf

@@ -62,6 +62,6 @@ resource "aws_security_group" "sg_rds" {
     from_port   = 0
     to_port     = 0
     protocol    = "-1"
-    cidr_blocks = ["0.0.0.0/0"]
+    cidr_blocks = data.terraform_remote_state.networking.outputs.private_subnets
   }
 }