Add S3 scan object Terraform module to Vault file storage

[patheard]

Summary

Add the S3 scan object Terraform module to the forms-${var.env}-vault-file-storage bucket to enable ClamAV file scanning on all newly created S3 objects.

The module behaves as follows:

1. When an S3 object is created in the bucket, it triggers a scan using Scan Files ClamAV endpoint.
2. This marks the S3 object scanning status as in_progress using object tags.
3. Once Scan Files has completed the scan, it publishes the scan verdict to an SNS topic, which causes the lambda to update the S3 object tag with the scan verdict.

Related

• File scanning proof of concept: trigger scan of new S3 objects #219