[PRMP-835] Replace null values in policy docs with empty strings and compact() list (#505)

Author: adamwhitingnhs

infrastructure/lambda-mns-notification.tf

@@ -8,8 +8,8 @@ module "mns-notification-lambda" {
     module.sqs-mns-notification-queue[0].sqs_write_policy_document,
     module.lloyd_george_reference_dynamodb_table.dynamodb_write_policy_document,
     module.lloyd_george_reference_dynamodb_table.dynamodb_read_policy_document,
-    local.is_production ? null : module.document_review_dynamodb_table[0].dynamodb_write_policy_document,
-    local.is_production ? null : module.document_review_dynamodb_table[0].dynamodb_read_policy_document,
+    local.is_production ? "" : module.document_review_dynamodb_table[0].dynamodb_write_policy_document,
+    local.is_production ? "" : module.document_review_dynamodb_table[0].dynamodb_read_policy_document,
     aws_iam_policy.ssm_access_policy.policy,
     module.ndr-app-config.app_config_policy,
     aws_iam_policy.kms_mns_lambda_access[0].policy,

infrastructure/modules/lambda/main.tf

@@ -160,7 +160,7 @@ resource "aws_iam_role" "lambda_execution_role" {
 }
 
 data "aws_iam_policy_document" "merged_policy" {
-  source_policy_documents = concat(var.iam_role_policy_documents, [data.aws_iam_policy_document.lambda_kms_access.json])
+  source_policy_documents = concat(compact(var.iam_role_policy_documents), [data.aws_iam_policy_document.lambda_kms_access.json])
 }
 
 resource "aws_iam_policy" "combined_policies" {