Remove clamv_db_efs

Description:
- https://github.com/alphagov/govuk-infrastructure/pull/725/files introduced the EBS CSI Driver which created EFS for ClamAV
- Next https://github.com/alphagov/govuk-helm-charts/pull/508/files allowed ClamAV to talk to EFS over NFS exposing over clamav-db-govuk.integration.govuk-internal.digital
- However this didn’t work so ClamAV was switched to use the EFS CSI driver in https://github.com/alphagov/govuk-helm-charts/pull/514/files. But this removes the reference to clamav-db-govuk.integration.govuk-internal.digital
- #790 removes the EFS CSI driver
- Next https://github.com/alphagov/govuk-helm-charts/pull/572/files makes ClamAV share the EFS instance via the same NFS mount as asset manager.
- Now there is a dangling reference to ClamAV EFS instance which can be safely removed as nothing references it anymore.
- As part of alphagov/govuk-helm-charts#1883

terraform/deployments/cluster-infrastructure/outputs.tf

@@ -118,10 +118,6 @@ output "monitoring_namespace" {
   value       = local.monitoring_namespace
 }
 
-output "clamav_db_efs_id" {
-  value = aws_efs_file_system.clamav-db.id
-}
-
 output "public_nat_gateway_ips" {
   value = [for eip in aws_eip.eks_nat : eip.public_ip]
 }

terraform/deployments/govuk-publishing-infrastructure/asset_manager_efs.tf

@@ -26,7 +26,7 @@ resource "aws_efs_file_system" "assets_efs" {
   creation_token = "blue-assets"
   tags = {
     "Name"        = "asset-manager"
-    "Description" = "Asset Manager and Whitehall attachments are stored here temporarily for malware scanning before being transferred to S3."
+    "Description" = "ClamAV database configuration is stored here. Asset Manager and Whitehall attachments are stored here temporarily for malware scanning before being transferred to S3."
   }
 }