Ambiguity in $components runtime expressions

We have ambiguity for: `"$components." name / "$components.parameters." parameter-name`

Both parse as `$components.` + `name`:

```
$components.parameters.foo → name = "parameters.foo"
$components.schemas.Pet    → name = "schemas.Pet"
```

The "$components.parameters." parameter-name alternative is never reached because "$components." name matches first with the greedy name = *( CHAR ) rule.
