Added maintenance window for prod postgress

- Configured the maintenance window to occur on Sunday at 2 AM when there is minimal application traffic. This ensures that any necessary updates or maintenance tasks are performed during a low-traffic period, minimizing impact on users.

terraform/application/config/production/variables.tfvars.json

@@ -1,6 +1,11 @@
 {
   "app_environment": "production",
   "app_replicas": 2,
+  "azure_maintenance_window": {
+    "day_of_week": 0,
+    "start_hour": 2,
+    "start_minute": 0
+  },
   "cluster": "production",
   "dqt_api_url": "https://teacher-qualifications-api.education.gov.uk",
   "enable_logit": true,

terraform/application/databases.tf

@@ -29,4 +29,6 @@ module "postgres" {
   use_azure               = var.deploy_azure_backing_services
   azure_enable_monitoring = var.enable_monitoring
   azure_extensions        = ["pg_stat_statements", "pgcrypto"]
+
+  azure_maintenance_window = var.azure_maintenance_window
 }

terraform/application/variables.tf

@@ -17,6 +17,15 @@ variable "azure_resource_prefix" {
   type = string
 }
 
+variable "azure_maintenance_window" {
+  type = object({
+    day_of_week  = number
+    start_hour   = number
+    start_minute = number
+  })
+  default = null
+}
+
 variable "azure_sp_credentials_json" {
   type    = string
   default = null