fix: Remove secret rotation_rules for TF v5.0+

Fixes #18

Previously we specified `rotation_rules` in our Secrets with an
intended frequency but didn't actually provide a Lambda to perform
the update. Terraform 5.0 (released 2023) removed this deprecated
parameter, and the replacement `aws_secretsmanager_secret_rotation`
resource doesn't seem able to apply specifying only a schedule but
not a Lambda ARN. Therefore, simply removed our old rotation_rules
blocks for forward compatibility with Terraform v5.0+

Author: athewsey

infra/modules/secrets/main.tf

@@ -9,11 +9,6 @@ resource "aws_secretsmanager_secret_version" "cognito_client_secret" {
 
 resource "aws_secretsmanager_secret" "zendesk_credentials" {
   name = "zendesk_credentials"
-  
-  # Basic rotation schedule only - no managed rotation function
-  rotation_rules {
-    automatically_after_days = 90
-  }
 }
 
 resource "aws_secretsmanager_secret_version" "zendesk_credentials" {
@@ -40,10 +35,6 @@ resource "aws_secretsmanager_secret_version" "langfuse_credentials" {
 
 resource "aws_secretsmanager_secret" "gateway_credentials" {
   name = "gateway_credentials"
-  
-  rotation_rules {
-    automatically_after_days = 90
-  }
 }
 
 resource "aws_secretsmanager_secret_version" "gateway_credentials" {