Cannot deregister a service which was registered via Terraform without using Terraform

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#### Overview of the Issue

When a service is registered via Terraform, it appears to be impossible to remove said service without also using Terraform. This is a problem for when a state file has been lost 🙃

#### Reproduction Steps

1. Register a service via Terraform
2. Try to deregister the service using `consul services deregister` or to remove the node running the service using `consul force-leave`

### Consul info for both Client and Server

The client doesn't exist in my case, the service just exists without an actual running server running it.

The server is running version 1.7.1.

### Operating system and Environment details

Using CentOS7 on Amd64 hardware.

### Log Fragments

Nothing gets printed when trying to run my example commands.

Start by reproducing the Terraform registration, then run `consul services deregister` and `consul force-leave` against Consul 1.7.1 on CentOS 7. Check how each command handles a service with no running client or server. Done means a service registered through Terraform can be removed without access to its Terraform state.

Written by the indexing model from the issue text.