Go to definition and autocompletion do not work when using module rec

### Issue
when using `module rec` "go to definition" and autocompletion do not work

### Demo
https://github.com/antonstefanov/delme-reason-ls-repro/blob/master/src/Demo.re

```reason
// A.re
module Child1 = {
let concat = (a, b) => a ++ b;
let concat2 = (a, b) => a ++ b;
};
module rec Child2: {let concat: (string, string) => string;} = {
let concat = (a, b) => a ++ b;
};
```
```reason
// Demo.re
// autocompletion, go to definition work
let a = A.Child1.concat("a", "b");
// Child2 is a rec module
// autocompletion, go to definition do NOT work
let b = A.Child2.concat("a", "b");
```

(possibly related, so I won't open a new issue, but there's also an external library in `External.re` and go to definition does not work either)

Start with the linked Demo.re reproduction and compare the working A.Child1.concat case with the failing A.Child2.concat module rec case. Trace the language-server handling of these definitions and the External.re example; done means go-to-definition and autocompletion work for the recursive module case without regressing the existing case.

Written by the indexing model from the issue text.