LSP: fix document links for library files
`src/test/contracts/lsp/registry.jsligo` contains
```
#import "@ligo/bigarray/lib/bigarray.mligo" "Bigarray"
```
and document link for this import directive is incorrect. But "go to definition" for e.g. `Bigarray.fill` points me to some file. We should use the the same file as a document link target.
Ideally, we should find the project root for that and pass it to get-scope as well, see #1657.
We can also check if file exists for project root equal to all parent directories, or use VSCode root by default with option to override it in workspace settings
issue