feat: Give VPC Access Agent Service Account for Cloud Run permissions on Shared VPC (#615)

* Grant compute.networkUser role to Serverless VPC Access Service Agent

* update comments

Author: derhally

modules/shared_vpc_access/main.tf

@@ -26,6 +26,7 @@ locals {
     "dataproc.googleapis.com" : format("service-%s@dataproc-accounts.iam.gserviceaccount.com", local.service_project_number),
     "dataflow.googleapis.com" : format("service-%s@dataflow-service-producer-prod.iam.gserviceaccount.com", local.service_project_number),
     "composer.googleapis.com" : format("service-%s@cloudcomposer-accounts.iam.gserviceaccount.com", local.service_project_number)
+    "vpcaccess.googleapis.com" : format("service-%s@gcp-sa-vpcaccess.iam.gserviceaccount.com", local.service_project_number)
   }
   gke_shared_vpc_enabled      = contains(var.active_apis, "container.googleapis.com")
   composer_shared_vpc_enabled = contains(var.active_apis, "composer.googleapis.com")
@@ -39,6 +40,8 @@ locals {
   if "dataflow.googleapis.com" compute.networkUser role granted to dataflow  service account for Dataflow on shared VPC subnets
   See: https://cloud.google.com/kubernetes-engine/docs/how-to/cluster-shared-vpc
        https://cloud.google.com/dataflow/docs/concepts/security-and-permissions#cloud_dataflow_service_account
+  if "vpcaccess.googleapis.com" compute.networkUser role granted to Serverless VPC Access Service Agent on shared VPC subnets
+  See: https://cloud.google.com/run/docs/configuring/connecting-shared-vpc#grant-permissions
  *****************************************/
 resource "google_compute_subnetwork_iam_member" "service_shared_vpc_subnet_users" {
   provider = google-beta