feat: Add database tags per az

Author: kahirokunn

main.tf

@@ -461,6 +461,7 @@ resource "aws_subnet" "database" {
     },
     var.tags,
     var.database_subnet_tags,
+    lookup(var.database_subnet_tags_per_az, element(var.azs, count.index), {})
   )
 }
 

variables.tf

@@ -558,6 +558,12 @@ variable "database_subnet_tags" {
   default     = {}
 }
 
+variable "database_subnet_tags_per_az" {
+  description = "Additional tags for the database subnets where the primary key is the AZ"
+  type        = map(map(string))
+  default     = {}
+}
+
 variable "database_subnet_group_tags" {
   description = "Additional tags for the database subnet group"
   type        = map(string)