whitespace between column names in ref causes Error: Invalid parameter name crash
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### Summary

When defining a @ref like this:

```
@ref typeA via:(id_1,id_2)->types_a.a(id_1, id_2) singular
```

Causes the following crash:

```
Error occurred whilst building the schema (phase = GATHER; attempt 1). We'll try again in 100ms.
  Error: Invalid parameter name
```

Where as removing the white space between the id_1 and id_2 like so:

```
@ref typeA via:(id_1,id_2)->types_a.a(id_1,id_2) singular
```

Seems to work fine.

<!-- A brief summary of the problem. -->

### Steps to reproduce

Add a @ref comment with spaces between the column fields. (e.g. `column_1, column_2`)

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### Expected results

<!-- Outline what you expected to see -->

I expect it to work with or without spaces after the comma between columns.

### Actual results

It crashes when spaces are between the column fields.

<!-- Outline the actual results -->

### Additional context

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      operating system, Node, PostgreSQL, Redis, etc. as relevant), software
      versions (from `yarn.lock`) or similar, plugins in use, database schema
      if relevant, bundler (if any). -->

### Possible Solution

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