deploy gets stuck and doesn't print anything

### Steps to reproduce
```cap production deploy```
and that's it, just gets stuck forever until I abort it

### Expected behavior
- Continue with deploying
- It must to print a TimeOut error log or something else

### Actual behavior
When I run: `cap production deploy` it shows nothing, just keeps waiting
But when I run: `cap production deploy --trace` it shows this:
```
** Invoke production (first_time)
** Execute production
** Invoke load:defaults (first_time)
** Execute load:defaults
** Invoke rbenv:validate (first_time)
** Execute rbenv:validate
```

### System configuration
https://gist.github.com/anyelopetit/7320fc8141554ea4b75ec88bb02f8132

Reproduce `cap production deploy` and compare it with `cap production deploy --trace`; the trace stops at `rbenv:validate`. Start by investigating that entry point and the system configuration in the linked gist. Done means deployment no longer hangs silently and reports a timeout or other actionable error.

Written by the indexing model from the issue text.