Fix RJSON's object parsing

[bobrippling]

Found in espruino/BangleApps#3114, object parsing exits early for strings with an empty object:

>JSON.parse('{"c":1}')
={  }

Or if we've parsed in a relaxed mode and hit a string, I'd expect us to exit with that object on hitting a string key, but I'm not sure how to enable the relaxed mode parsing from an espruino prompt.

Closes espruino/BangleApps#3114

[gfwilliams]

Thanks! Wow, sorry - that was a really stupid bug to introduce!

[bobrippling]

Thanks for the follow up too! I need to get setup for running locally, was flying blind with that one

[gfwilliams]

:) No problem! If you're on Windows it's worth installing WSL - once that's installed, you can git clone it and it should 'just work' with make