feat: support multiple service accounts to assume role

Author: msvticket

main.tf

@@ -144,7 +144,7 @@ data "aws_iam_policy_document" "assume_role" {
       condition {
         test     = "StringLike"
         variable = join(":", [var.iam_irsa_openid_connect_provider_url, "sub"])
-        values   = [var.iam_irsa_service_account]
+        values   = compact(concat([var.iam_irsa_service_account], var.iam_irsa_service_accounts))
       }
     }
   }

variables.tf

@@ -142,6 +142,12 @@ variable "iam_irsa_service_account" {
   description = "Kubernetes ServiceAccount to allow to access the Elastic Domain via IRSA"
 }
 
+variable "iam_irsa_service_accounts" {
+  type        = list(string)
+  default     = []
+  description = "Kubernetes ServiceAccounts to allow to access the Elastic Domain via IRSA"
+}
+
 variable "zone_awareness_enabled" {
   type        = bool
   default     = true