Need more details when emitting Error: unexpected end of JSON input

**What is the problem this feature would solve? Please describe.**
Add details to `Error: unexpected end of JSON input`

**Describe the solution you'd like**
We need more information when this happens (quite often) and it's nearly impossible to debug.

```
doctl serverless deploy . --remote-build

Error: unexpected end of JSON input
```

Should include a stack trace, or some extra metadata about the the issue.