No drift detection in plan

[tsmalls93]

When I make changes to the infrastructure, I expect Terraform to detect this in the plan. For example, I deleted a port from an SLB server in the A10 GUI, but Terraform did not detect any changes. I tried extracting the port into a thunder_slb_server_port resource, but that resulted in an error that said "axapi failure:CM:err=Object slb server port {90,tcp} does not exist."