Ruru: Websocket endpoint not followed?
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### Summary

In ruru, typing:
```
$ npx ruru@beta -Pe http://localhost:5173/graphql  -S -s ws://localhost:4000/graphql
```
ends up in the websocket entry `ws://localhost:1337/graphql` being used (I can see this in an error message by firefox).

### Steps to reproduce

Just type the above command and try to subscribe to a graphql server.

### Expected results

I should use the port 4000.

### Actual results

It uses the port 1337

<!-- Outline the actual results -->
