Unusual error message when attempting to track table through API

### Version Information

Server Version: docker image v2.6.1

### Environment

OSS

### What is the current behaviour?

I'm attempting to track a table with the API. I issued a request like the following:

```
{"type":"pg_track_table","args":{"source":"default","table":{"schema":"sgd6296","name":"update_source_vault_authorization"}}}
```

and ended up getting the following error:

```
Inconsistent object: cannot include "block$" in the GraphQL schema because it is not a valid GraphQL identifier
```

However, when I examine this schema in hasura, I don't see a table called `block$`.

Here are the tracked tables for the schema:

and here are the untracked tables for the schema:

That being said, there are other schemas in my database with tables called `block` but I'm not sure where the `$` suffix is coming from:

### What is the expected behaviour?

I expect the call to succeed or to fail for some other reason, not because of an unknown table in that specified schema.

### How to reproduce the issue?

I don't know.

Start by reproducing the pg_track_table API request against the reported v2.6.1 environment and inspect how the specified PostgreSQL table is converted into the GraphQL schema. Trace where the unexpected block$ identifier is introduced; done means either the tracking request succeeds or returns an error that accurately identifies the actual cause and table.

Written by the indexing model from the issue text.